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THE LIBRARY OF USEFUL STORIES
Image: A COTTON FIELD IN TEXAS
THE STORY OF THE COTTON PLANT
BY
FREDERICK WILKINSON, F. G. S.
DIRECTOR OF THE TEXTILE AND ENGINEERING SCHOOL, BOLTON AND CO-AUTHOR OF ELEMENTS OF COTTON SPINNING
WITH THIRTY-EIGHT ILLUSTRATIONS
NEW YORK AND LONDON D. APPLETON AND COMPANY 1912
COPYRIGHT, 1898, 1902, BY D. APPLETON AND COMPANY.
Printed in the United States of America
PREFACE.
In collecting the facts which will be found in this Story of the Cotton plant, the author has of necessity had to consult many books. He is especially indebted to Baines' "History of the Cotton Manufacture," French's "Life and Times of Samuel Crompton," Lee's "Vegetable Lamb of Tartary," Report of the U. S. A. Agricultural Department on "The Cotton Plant," and The American Cotton Company's Booklet on the Cylindrical Bale.
Mr. Thornley, spinning master at the Technical School, Bolton, has from time to time offered very important suggestions during the progress of this little work. The author is also deeply indebted to the late Mr. Woods of the Technical School, Bolton, who was good enough to photograph most of the pictures which illustrate this book, and without which it would have been impossible to make the story clear.
For permission to reproduce Fig. 3, the thanks of the author are due to Messrs. Sampson Low and Co., for Fig. 4, to Messrs. Longmans, Green and Co. For Figs. 5, 8, 9, 13, and 36, to Messrs. Dobson and Barlow, Ltd., Bolton. For Fig. 7, viz., the Longitudinal and Transverse Microphotographs of Cotton Fibre, the author is much indebted to Mr. Christie of Mark Lane, London, who generously photographed them especially for this work. For Fig. 23, I am obliged to Mr. A. Perry, Bolton.
FRED WILKINSON.
TEXTILE AND ENGINEERING SCHOOL, BOLTON.
CONTENTS.
CHAPTER PAGE
I. ORIGIN, GROWTH, AND CHIEF CULTIVATED SPECIES OF COTTON PLANT 9
II. COTTON-PLANT DISEASES AND PESTS 34
III. CULTIVATION OF THE COTTON PLANT IN DIFFERENT COUNTRIES 39
IV. THE MICROSCOPE AND COTTON FIBRE 64
V. PLANTATION LIFE AND EARLY CLEANING PROCESSES 72
VI. MANIPULATION OF COTTON IN OPENING, SCUTCHING, CARDING, DRAWING, AND FLY-FRAME MACHINES 82
VII. EARLY ATTEMPTS AT SPINNING, AND EARLY INVENTORS 112
VIII. FURTHER DEVELOPMENTS—ARKWRIGHT AND CROMPTON 126
IX. THE MODERN SPINNING MULE 146
X. OTHER PROCESSES IN COTTON SPINNING 160
XI. DESTINATION OF THE SPUN YARN 176
INDEX 189
LIST OF ILLUSTRATIONS.
FIGURE PAGE
1. A Cotton Field in Texas Frontispiece
2. Bobbins of Cotton Thread 10
3. The Vegetable Lamb of Tartary 13
4. Gossypium Barbadense 24
5. An Indian Cotton field 53
6. Microscope in position for drawing objects 65
7. Transverse and Longitudinal Sections of Cotton Fibre 67
8. Indian women with Roller gin 75
9. Self-acting Macarthy Cotton gin 78
10. Bales from various Cotton-growing countries 80
11. Cylindrical Rolls of Cotton 81
12. Bale Breaker or Puller 87
13. Double opener with Hopper Feed 89
14. Scutching Machine with lap at the back 92
15. Two views of the Carding Engine 95
16. Lap, Web, and Sliver of Cotton 99
17. Drawing Frame, showing eight slivers entering, and one leaving the machine 103
18. Intermediate Frame (Bobbin and Fly Frame) 108
19. Twist put in Cotton by the hand 115
20. Jersey spinning wheel 117
21. Hargreaves' Spinning Jenny 124
22. Arkwright's Machine 130
23. "The Hall ith Wood" 136
24. Crompton's Spinning Mule 141
25. Portrait of Samuel Crompton 145
26. Mule Head showing Quadrant 148
27. Mules showing "Stretch" of Cotton yarn 150
28. Mule showing action of Faller Wires 154
29. Mule Head showing Copping Rail 159
30. Ring Spinning Frame 161
31. Combing Machine 170
32. Sliver Lap Machine 173
33. Ribbon Lap Machine 175
34. Reeling Machine 179
35. Bundling Machine 180
36. Quick Traverse Winding Frame 182
37. Ring Doubling Machine 184
38. Engine House, showing driving to various storeys 186
THE STORY OF THE COTTON PLANT.
CHAPTER I.
ORIGIN, GROWTH, AND CHIEF CULTIVATED SPECIES OF COTTON PLANT.
In the frontispiece of this little work is a picture of a cotton field showing the plants bearing mature pods which contain ripe fibre and seed, and in Fig. 2 stands a number of bobbins or reels of cotton thread, in which there is one having no less than seventeen hundred and sixty yards of sewing cotton, or one English mile of thread, on it. As both pictures are compared there appears to be very little in common between them, the white fluffy feathery masses contained in the pods shown in the one picture, standing in strange contrast to the strong, beautifully regular and even threads wound on the bobbins pictured in the other.
From cotton tree to cotton thread is undoubtedly a far cry, but it will be seen further on that the connection between the two is a very real and vital one.
Now it is the main purpose of this book to unfold the wonderful story of the plant, and to fill in the details of the gap from tree to thread, and to trace the many changes through which the beautiful downy cotton wool passes before it arrives in the prim looking state of thread ready alike for the sewing machine or the needle of a seamstress.
Image: FIG. 2.—Bobbins of cotton thread.
Remembering that the great majority of the readers of this little book must of necessity be quite unaccustomed to trade terms and technical expressions, the author has endeavoured to present to his readers in untechnical language a simple yet truthful account of the many operations and conditions through which cotton is made to pass before reaching the final stages.
Nature provides no lovelier sight than the newly opened capsules containing the pure white and creamy flocculent masses of the cotton fibre as they hang from almost every branch of the tree at the end of a favourable season.
And how strange is the story of this plant as we look back through the centuries and listen to the myths and fables, almost legion, which early historians have handed down to us or imaginative travellers have conceived. There is, however, every reason to believe that in the far distant ages of antiquity this plant was cultivated, and yielded then, as it does now, a fibre from which the inhabitants of those far-off times produced material with which to clothe their bodies.
It will not be considered out of place if some of the early beliefs which obtained among the peoples of Western Asia and Europe for many years are related.
Like many other things the origin of the Cotton plant is shrouded in mystery, and many writers are agreed that it originally came from the East, but it will be seen later on that equally strong claims can be presented from other countries in the Western Hemisphere. Many of us have been amused at the curious ideas which people, say of a hundred years ago, had of the Coral Polyp.
Even to-day children may be heard singing in school,
"Far adown the silent ocean Dwells the coral insect small"!
Not a few of the early naturalists believed that the Coral was a plant and while living in the sea water it was soft, and when dead it became hard!
We smile at this, of course, but it was not until actual investigation on the spot, as to what the Coral was, that the truth came out.
It was then discovered to be an animal and not a plant, and that during life its hard limy skeleton was covered by soft muscular tissue, which, when decomposing, was readily washed away by the sea, leaving the hard interior exposed as coral.
When the absurd beliefs are read which found credence among all classes of the people during the middle ages, and down even to the end of the seventeenth century, as to what the cotton boll or pod was, the reader is inclined to rub his eyes and think surely he must be reading "Baron Munchausen" over again, for a nearer approach to the wonderful statements of that former-fabled traveller it would be difficult to find than the simple crude conceptions which prevailed of the growth, habits, and physical characteristics of the Cotton plant.
The subject of the early myths and fables of the plant in question has been very fully treated by the late Mr. Henry Lee, F. L. S., who was for a time at the Brighton Aquarium. His book, the "Vegetable Lamb of Tartary," shows indefatigable research for a correct explanation of the myth, and after a strictly impartial inquiry he comes to the conclusion that all the various phases which these fabulous concoctions assumed, had their beginnings in nothing more or less than the simple mature pod of the Cotton plant.
It will not be necessary to consider here more than one or two of these very curious beliefs about cotton. By some it was supposed that in a country which went by the name "The Tartars of the East," there grew a wonderful tree which yielded buds still more wonderful. These, when ripe, were said to burst and expose to view tiny lambs whose fleeces gave a pure white wool which the natives made into different garments.
By and by, a delightfully curious change took place, and it is found that the fruit which was formerly said to have the little lamb within, was now changed into a live lamb attached to the top of the plant. Mr. Lee says: "The stem or stalk on which the lamb was suspended above the ground, was sufficiently flexible to allow the animal to bend downward, and browse on the herbage within its reach. When all the grass within the length of its tether had been consumed, the stem withered and the plant died. This plant lamb was reported to have bones, blood, and delicate flesh, and to be a favourite food of wolves, though no other carnivorous animal would attack it."
Image: FIG. 3.—The vegetable lamb of Tartary.
In Fig. 3 is shown Joannes Zahn's idea of what this wonderful "Barometz or Tartarian lamb" was like. Now, mainly through an imaginative Englishman named Sir John Mandeville, who lived in the reign of Edward III., did this latter form of the story find its way into England.
This illustrious traveller left his native country in 1322, and for over thirty years traversed the principal countries of Europe and Asia. When he came home he commenced to write a history of his remarkable travels. In these are found references to the Cotton plant, and so curious an account does he give of it, that it has been considered worth reproduction in his own words: "And there growethe a maner of Fruyt, as though it weren Gourdes: and whan ther been rype men kutten hem ato, and men fynden with inne a lyttle Best, in Flesche, in Bon and Blode, as though it were a lytylle Lomb with outen Wolle. And men eten both the Frut and the Best; and that is a great Marveylle. Of that Frute I have eaten; alle thoughe it were wondirfulle, but that I knowe well that God is Marveyllous in his Werkes."
No wonder that many accepted his account of the "Vegetable Lamb" without question. When a nobleman of the reputation of Sir J. Mandeville stated that he had actually eaten of the fruit of the Cotton, was there any need for further doubt?
It appears, however, that contemporary with Mandeville was another traveller, an Italian Friar, named Odoricus, who also had travelled in Asia and heard of the plant which yielded cotton. He, too, fell a prey to the lamb theory. Many other writers and travellers followed, all more or less believing in the plant animal theory. However, in 1641, Kircher of Avignon in describing cotton declared it to be a plant. And so the story for years passed through many changes. First one would assert what he considered to be the right solution, and this was immediately challenged by the next investigator, so that assertion and contradiction followed each other in quick succession.
In 1725, however, a German doctor named Breyn communicated with the Royal Society on the subject of the "Vegetable lamb," emphatically stating the story to be nothing more or less than a fable. He very naively remarked that "the work and productions of nature should be discovered, not invented," and he threw doubts as to whether those who had written about the mythical lamb had ever seen one.
When the writings and dissertations of Mandeville, Odoricus and others are carefully considered, these conclusions force themselves upon us: that direct personal observation must have played a very minor part in the attempt to get at the truth in connection with the origin and growth of the Cotton plant.
Their statements stand in very sharp contrast with those of writers who lived before the Christian era commenced. Of these, mention must be made of Herodotus, surnamed the Father of History.
This celebrated Greek historian and philosopher was born, B.C. 484, in Halicarnassus in Greece. In his book of travels he speaks of the Cotton plant. It appears, mainly owing to the tyrannical government of Lygdamis, he left his native land and travelled in many countries in Europe, Asia, and Africa. He appears to have at least determined, that he would only write of those things of which he had intimate knowledge, and would under no circumstances take for granted what he could not by personal observation verify for himself. In speaking of India and the Cotton plant, he says: "The wild trees in that country bear for their fruit fleeces surpassing those of sheep in beauty and excellence, and the natives clothe themselves in cloths made therefrom." In another place he refers to a present which was sent by one of the kings of Egypt, which was padded with cotton. He also describes a machine for separating the seed from the fibre or lint. Compared with our modern gins, as they are called, this machine was exceedingly primitive and simple in construction.
There is not the slightest doubt that the first reliable information of the physical characters of the fibre and its uses was conveyed into Europe by the officers of the Emperor Alexander. One of his greatest Admirals, named Nearchus, observed the growth of cotton in India, and the use to which it was put, especially the making of sheets, shirts and turbans.
Perhaps one of the most careful observers that lived before the Christian era commenced, was Theophrastus, who wrote some strikingly correct things about the Cotton plant of India three centuries before Christ!
In describing the tree he said it was useful in producing cotton which the Indians wove into garments, that it was not unlike the dog rose, and that the leaves were somewhat like the leaves of the mulberry tree. The cultivation of the plant was also very correctly noted as to the rows in which the cotton seeds were placed, and as to the distances to which these rows were set. According to Dr. Royle, however, reference is made to cotton in the "Sacred Institutes of Manu" so frequently that the conclusion is admitted that cotton must have been in frequent use in India at that time, which was 800 B.C.
As was to be expected, Persia very early had cottons and calicoes imported from India. In the sixth verse of the first chapter of Esther definite reference is made to the use to which cotton was put at the feasts which King Ahasuerus gave about 519 B.C. "White, green, and blue hangings" are said to have been used on this occasion, and from authorities who have specially investigated this subject, we are told that the hangings mentioned were simply white and blue striped cottons. This would also confirm the statement that dyeing is one of the oldest industries we have.
It appears that the Greeks and Romans in good time learned to value goods made of cotton, and soon followed the Oriental custom of erecting awnings or coverings for protection from the sun's rays. The Emperor Caesar is said to have constructed a huge screen extending from his own residence along the Sacred Way to the top of the Capitoline Hill. The whole of the Roman Forum was also covered in by him in a similar way. Coverings for tents, sail cloth made from cotton, and fancy coverlets were also in use among the people of these stirring times.
And now comes the important question: Was cotton indigenous to India in these very early times? and was it carried and afterwards planted in Egypt, Africa, and America?
As an attempt is made to successfully answer this question, our minds are thrown back to the time when Christopher Columbus, a Genoese, having heard of India, desired to find a new way to that country. Comparatively poor himself, he was unable to equip an expedition, and laid his scheme before the Council of Genoa. They declined to have anything to do with it, and he is found next presenting his case to the King of Portugal. Here he alike failed, and he ultimately applied to the King and Queen of Spain, when he met with success.
The 3rd of August, 1492, found him fully equipped with two ships, and on his way west to find a new way to India. He first touched the Bahamas thirty days after setting sail from Europe, and to his astonishment he was met by the natives, who came out to meet him in canoes, bringing with them cotton yarn and thread for the purpose of barter. In Cuba he was surprised to find hammocks made from cotton cord in very general use. What Columbus observed in the West Indies as to the growth and manufacture of cotton, was found afterwards to be by no means confined to these islands, but that in South and Central America the natives were quite accustomed both to the growth and manufacture of cotton.
Indisputable evidence can be presented to prove that the ancient civilisations of Mexico, Peru, and Central America, were well acquainted with cotton. When Peru was subjugated in 1522 by Pizarro, the manufacture of cotton was in a flourishing condition.
Similarly when Mexico fell into the hands of Cortez in 1519, he too found that the use of cotton was very general. So delighted was he at what he saw of the quality and beauty of their manufactured goods, that he had no hesitation in dispatching to Europe a present consisting of mantles, to the Emperor Charles V.
Five years after Columbus started on his momentous voyage, another expedition under Vasco da Gama set out from the Tagus to make the voyage to India by the way of the Cape of Good Hope.
Immediately Gama had safely reached India, there were others who quickly desired to follow, and in 1516 another adventurous Spaniard on his way to India called at S. Africa, and found the natives wearing garments made of cotton.
There is therefore no reason to question the statement which has repeatedly been made, that at least three centres are known in which the Cotton plant from very early times has been indigenous, and that the peoples of these countries were well acquainted with the property and uses of the cotton wool obtained from the plant. An average of more than 1,000,000 bales, each weighing 500 lbs., are exported from Egypt every year, and the question has been raised whether the cultivation of the plant in Egypt can be said to date far back. This is not so. The fibre almost exclusively used by the ancient Egyptians was flax, and the nature of the garments covering the mummies of the ancient Egyptians has been satisfactorily decided by the microscope. It is very probable that the cultivation of the plant at the beginning of the thirteenth century was carried on purely for the purpose of ornamental gardening, and even when the seventeenth century was fairly well advanced, the Egyptians still imported cotton.
The nineteenth century, however, has seen important developments in the cultivation of cotton in Egypt, and now the position attained by this country is only outdistanced by the United States and India.
The Botany of Cotton.—Botanists tell us that the vegetable kingdom is primarily divided into three great classes—viz., (1) Dicotyledons; (2) Monocotyledons; and (3) Acotyledons.
Now these names solely refer to the nature and form of the seeds produced by the plants, and by the first it is understood that a single seed is divisible into two seed lobes in developing. In the case of the second, the seed is formed only of one lobe, and in the third the seed is wanting as a cotyledon, but the method of propagation is carried on by what are called spores. We have examples of the last-named class in the ferns, lycopods and horsetail plants. The first two of the above-named classes have been well called Seed plants. These are again broken up into divisions, to which the name Natural Orders has been given. Most of us know, as the following are examined, Anemone, Buttercup, Marsh Marigold, Globe Flower, and Larkspur, that they have the same general structural arrangement, but in many particulars they differ. Thus these natural orders are again subdivided into genera, and a still further subdivision into species is made.
The Cotton plant is put in the genus Gossypium, which is one falling into the natural order Malvacae, and which is one of a very large number forming an important division of the dicotyledons where the stamens are found to be inserted below the pistil, and where the corolla is composed of free separate petals, and where the plant has a flower bearing both calyx and corolla. So far as numbers are concerned, the Malvacae cannot be said to be important, but few genera being known to fall into this order. Three are familiar at least—viz., the Marsh Mallow, which was formerly used a great deal in making ointment; the Musk Mallow, and the Tree Mallow. The most important genus in this order is the Gossypium. This name was given to the Cotton plant by Pliny, though the reasons for so doing are not clear. Very many species are known to exist at the present time, and this is not to be wondered at, when the area in which the plant is cultivated is so vast, and coupled with the fact that the plant is susceptible to the slightest change and "sports" most readily.
Differences of soil, climate, position with regard to the sea board, and variations in the method of cultivation could only be expected to result in the species being exceedingly numerous. It is not surprising, therefore, to find that no two botanists agree as to the number of species comprising the Gossypium family. A list, however, of the commoner varieties found in various cotton-growing areas of the globe will be given, but before doing so, it is deemed advisable to give a general botanical description of the plant.
The Gossypium is either herbaceous, shrubby, or treelike, varying in height from three to twenty feet. In some cases it is perennial; in most, as in the cultivated species, it is an annual or biennial. A few examples are noted for the vast number of hairs found everywhere on the plant, and on almost every part of the plant also, there may be observed black spots or glands. Usually the stem is erect, and as a rule the Cotton plant in form is not unlike the fir tree, that is, its lower branches are wider than those above, and this gradual tapering extends to the top of the tree. In consequence of this it is said to be terete. The leaves are alternate, veined and petiolated, that is, they have a leaf stalk connecting leaf and stem. In shape the leaves are cordate or heart-shaped, as well as sub-cordate, and the number of lobes found in the leaf varies from three to seven. The stipules or little appendages found on the petioles, resembling small leaves in appearance and texture, are generally found in pairs. The calyx is cup-shaped, and the petals of the flower are very conspicuous, and vary in colour according to the species, being brownish-red, purple, rose-coloured, and yellow. The petals, five in number, are often joined together at the base. The ovary is sessile, that is, it directly rests upon the main stem, and is usually three to five celled. The pod or capsule, which contains the seeds and cotton fibre, when ripe splits into valves, which vary in number from three to five. A characteristic feature of the pod is the sharp top point formed by the meeting of the pointed valves. The seeds are numerous and very seldom smooth, being usually thickly covered with fibrous matter known as raw cotton. As is well known, the wind performs a very important function in the dispersal of seeds. It is clear that when a seed is ready to be set free, and is provided by a tuft of hair, such as is seen on the cotton seed, dandelion and willow herb, it becomes a very easy matter for it to be carried ever so far, when a good breeze is blowing. Most of us have blown, when children, at the crown of white feathery matter in the dandelion, and have been delighted to see the tiny parachutes carrying off its tiny seed to be afterward deposited, and ultimately take root and appear as a new plant. Much in the same way, before it was cultivated, the Cotton plant perpetuated its own species. It should be added that the root of the Cotton plant is tap shaped, and penetrates deeply into the earth.
It would be well nigh impossible to enumerate all the species which are now known in the Cotton plant family, and it is not proposed here to describe more than the principal types of the Gossypium. In a report prepared by Mr. Tracy of Mississippi, U. S. A., no less than one hundred and thirty varieties of American cotton are given. He says: "The word 'variety' refers exclusively to the various forms and kinds which are called varieties by cotton planters, and is not restricted to the more marked and permanent types which are recognised by botanists. Of botanical varieties there are but few, while of agricultural varieties there are an almost infinite number, and the names under which the agricultural varieties are known are many times greater than the recognisable forms." The Cotton plant most readily responds to any changes of climate, methods of cultivation, change of soil or of fertilizers. So that it is easy to understand in a plant so susceptible and prone to vary as is the cotton, that new species may in a few years be brought into existence, and especially by means of proper selection of the seed, and careful cultivation.
The chief commercial types of Gossypium are—1. Barbadense; 2. Herbaceum; 3. Hirsutum; 4. Arboreum; 5. Neglectum; 6. Peruvianum.
Gossypium Barbadense.—The fine long silky fibres of commerce are all derived from this species. It is indigenous to a group of the West Indian Islands named the Lesser Antilles. It gets its name from Barbadoes, one of the West Indies. At the present time it is cultivated throughout the Southern States of North America which border on the sea, in most of the West Indian Islands, Central America, Western Africa lying between the tropics, Bourbon, Egypt, Australia, and the East Indies. There is no doubt that the plant comes to its highest and most perfect state of cultivation when it is planted near the sea. Dr. Evans says: "It may be cultivated in any region adapted to the olive and near the sea, the principal requisite being a hot and humid atmosphere, but the results of acclimatisation indicate that the humid atmosphere is not entirely necessary if irrigation be employed, as this species is undoubtedly grown extensively in Egypt." The height of this species varies from 3 to 4 feet if cultivated as an annual, and from 6 to 8 feet if allowed to grow as a perennial. When in full leaf and flower, it is a most graceful-looking plant. Yarns having the finest counts, as they are called, are all spun from Sea Islands, which belongs to this class. When we are told that a single pound of this cotton is often spun into a thread about 160 miles long we can see that it must be exceedingly good and strong cotton to do this.
Image: FIG. 4.—The Gossypium Barbadense.
Lint is the name given to the cotton which remains when separated from the seeds. Every other American type of cotton gives a greater percentage of lint than the Sea Islands cotton, though it should be stated that the price per pound is greater than any other kind of cotton grown in the States. There are from six to nine seeds in each capsule and the prevailing colour is black. A cotton grown in Egypt and known by the name Gallini is of the Sea Islands type and has been produced from seed of the G. Barbadense. It should be added that the colour of the flower is yellow and that in India this plant is known by the name of Bourbon Cotton.
Gossypium Herbaceum.—As indicated by the name, this type is herbaceous in character, especially the cultivated type. When Lamarck classified this tree, he gave it the name Indicum because he considered most of the Indian types and some of the Chinese belonged to this particular species. India, too, is considered by Parlatore to have been the original home of the herbaceous type, and he specially fixes the Coromandel Coast as the first centre from which it sprang. There is much conflict of opinion in localising the primitive habitat of this type, and it is now thought that the present stock is probably the result of hybridisation of several species more or less related to each other. However, the areas in which this class of cotton grows are very numerous and extensive, for we find it growing in India, China, Arabia, Persia, Asia Minor, and Africa. A very characteristic feature of this plant is that it quickly decays after podding, when cultivated as an annual.
The Vine Cotton grown in Cuba belongs to the herbaceous type and is remarkable for its large pods, which contain an abnormal number of seeds. The so-called "Nankeen" cottons are said to be "Colour variations" of the herbaceous Cotton plant. Many varieties of Egyptian cottons are produced from this particular class, as well as the Surat cotton of India.
A feature which distinguishes this type is that the seeds are covered with two kinds of fibre, a long and short, the latter being very dense. The process of taking the longer fibre from the seed must be very carefully watched, as it becomes a troublesome matter to remove the shorter fibre when once it has come away from the seed with the longer. Hence great care should be taken in gathering this class of cotton. Another point which should not be lost sight of is, that the herbaceous type of Cotton plant readily hybridises with some other varieties and the result is a strain of much better quality.
Gossypium Hirsutum.—This variety is so called because of the hairy nature of every part of the plant, leaves, stems, branches, pods and seeds—all having short hairs upon them. By Dr. Royle it is considered a sub-variety of the Barbadense cotton, and by other American experts it is given as synonymous with G. Herbaceum. However this may be, the plant has certain well-defined characteristics which possibly entitle it to be considered as a distinct type. It has been asserted by a competent authority that the original habitat of this particular cotton was Mexico, and that from this country cultivators have imported it throughout the sub-tropical districts of the world.
It is also stated that longstapled Georgian Uplands cotton belongs to the Hirsutum variety. In fact most of the types cultivated in America fall into this class. Parlatore also considers it to be indigenous to Mexico, and states that all green seeded cotton which is so extensively cultivated has been obtained from this type originally. M. Deschamps, in describing the Hirsutum species, says it is divided into two varieties, one having green seeds, being of a hardier type, and the other having greyish seeds, being more delicate and growing in the more southern districts of the States.
Gossypium Arboreum.—This plant attains treelike proportions, hence the name Arboreum. In some cases it will grow as high as twenty feet. It is also known by the name G. Religiosum, because the cotton spun from this plant was used only for making threads which were woven into cloth for making turbans for the priests of India. Dr. Royle on one occasion while in that country was informed by the head gardener of a Botanical Garden at Saharunpore that this cotton was not used for making cloth for the lower garments at all, its use being restricted to turbans for their heads, as it was sacred to the gods. That is why it also received the name, "Deo Cotton."
One or two interesting features of this type may be pointed out. The colour of the flowers is characteristic, being brownish and purply-red and having a dark spot purple in colour near the base of the corolla, this latter being bell-shaped. Like the herbaceous type two kinds of fibre are found on the seed and great care is needed in the separation of them. Also, it should be pointed out that the fibres, in this class are with difficulty removed from the seed, clinging very tenaciously to it.
The Arboreum type is indigenous to India and along the sea board washed by the Indian Ocean. The fibre from this species is much shorter in average length than any of the preceding varieties.
Gossypium Neglectum.—This too is an Indian cotton, and according to Royle the celebrated and beautiful Dacca cotton which gives the famous muslins, as well as the long cloth of Madras, are made from cotton obtained from the Neglectum variety. An important feature of this plant is the small pod which bears the fibre and the small number of seeds contained in each septa of the capsule, being only from five to eight in number. Like some preceding forms, the seeds carry cotton of two lengths, the shorter of the two being ashy green in colour. The longer fibre is harsh to the touch and white in colour. In many points it is very similar to the Arboreum type and is considered by some botanists to be a cross between the Arboreum species and some other. It does not attain any great height, being often in bush form under two feet. The country of Five Rivers or the Punjaub, North West Provinces and Bengal, are the districts in India in which it is mostly cultivated as a field crop. It has a high commercial value, forming the main bulk of the cotton produced in the Bengal presidency. This plant is indigenous to India.
Gossypium Peruvianum.—So called because Peru was considered to be the habitat of this cotton. By some authorities this particular species is for all practical purposes synonymous with the first type described—viz., Barbadense. By others it is said to be closely allied to the Acuminatum variety, so named because of the pointed character of its capsules and leaves. Perhaps the most striking feature of this plant is the colour of the seeds, which is black. Another interesting point about the seeds is that they adhere closely to each other, and form a cone-like mass. Brazil is the home of this particular species, though it is cultivated here in two forms, as "Tree Cotton" and as "Herbaceous Cotton." The former is also known by the name Crioulo or Maranhao Cotton or short Mananams. It appears also that the Tree Cotton is one of the very few which does not suffer from the depredations of the cotton caterpillar. What is known as "Kidney Cotton" belongs to this species, which is sometimes named Braziliense. The name kidney is given because of the peculiar manner in which the seeds are arranged in the capsule, adhering together in each cell in the form of a kidney.
The most important countries in which it is grown are Brazil and Peru, though it is produced in other districts outside these countries, but not to any great extent.
A very curious cotton which receives the name of "Red Peruvian" is also produced in South America. On account of its colour, it has only a very limited sale. This is owing to the difficulty there is in blending or mixing it with any other cotton of similar quality.
Cottons known generally as Santos, Caera and Pernams are not of this species—viz., Gossypium Peruvianum, but belong to the first and second of the types already described.
The Strength of Cotton Fibres.—Mr. O'Neill some years ago made many experiments with a view to obtaining the strengths of the different fibres, and the following table compiled by him, will be of interest to the general reader.
Sea Islands 83.9 mean breaking strain in grains. Queensland 147.6 " " Egyptian 127.2 " " Maranham 107.1 " " Bengueld 100.6 " " Pernambuco 140.2 " " New Orleans 147.7 " " Upland 104.5 " " Surat (Dhollerah) 141.9 " " Surat (Comptah) 163.7 " "
From this table it is arguable that the strength of fibre varies according to the diameter, that is to say, the fibre with the thickest diameter carries the highest strain. The order, therefore, in which the fibres would fall, according to strength, would be, Indian, American, Australian, Brazilian, Egyptian, and Sea Islands last.
The Chemistry of the Cotton Plant.—Messrs. M'Bryde & Beal, Chemists in the Experimental Station in Tennessee, say, "As a rule our staple agricultural plants have not received the thorough, systematic chemical investigation that their importance demands." It would appear that until recent times the above statement was only too true. Now, however, the United States Government and others have instituted experiments on a large scale, and everything is now being done in the direction of research, with a view to improving the quality of this important plant.
A complete Cotton plant consists of roots, stems, leaves, bolls, seed and lint. Now if these six parts of the plant be weighed, they vary very much, proving that some of them are more exhaustive than others, so far as the fertilizing matters found in the soil are concerned. For example, if water be discarded in the calculation, though this takes up a fair percentage of the total weight, about 10, it is found that the roots take up by weight over 8 per cent. of the whole plant, stems over 23 per cent., leaves over 20, bolls over 14, seeds over 23, and lint only 10-1/2 per cent.
Now this statement is interesting as showing one or two important features. The weight of the seed is seen to be nearly a quarter of the whole plant, while the stems and leaves together take up nearly one half. A very small proportion by weight of the plant is taken by the lint.
A chemical analysis of the mature Cotton plant yielded the following substances:—
Water. Potash. Ash. Lime. Nitrogen. Magnesia. Phosphoric acid. Sulphuric acid. Insoluble matter.
Of ten analyses made with the cotton lint (which takes up about 10-1/2 per cent. of the whole) M'Bryde states that the average amount of water found was 6.77, ash 1.8, nitrogen .2, phosphoric acid .05, potash .85, lime .15, and magnesia .16.
He very pertinently remarks also "that if the lint were the only part of the plant removed from the land on which it is grown, cotton would be one of the least exhaustive of farm crops. The only other part which need be permanently lost to the soil is the oil, which also contains very small amounts of fertilising constituents." In connection with this he further says "that even when the seed is taken away along with the lint, cotton still removes smaller amounts of fertilising materials from the soil than either oats or corn." It should be borne in mind that the soil upon which cotton is cultivated lies fallow for a greater part of the year, and the fact of absence of cultivation, with consequent non-fertilising and non-enriching of land, must tend in the direction of soil exhaustion by the Cotton plant.
Another useful and important fact in connection with the Cotton plant is the medicinal use to which the roots are put. According to the American Journal of Pharmacy, the bark from the roots of the Cotton plant contain an active ingredient which in its effects is very much like ergot.
Chemical investigations have conclusively proved that the ripe fibre of the Cotton plant is composed of the following substances:—
Carbon, Hydrogen, Oxygen, and they tell us that when cotton is fully ripe it is almost pure cellulose.
Dr. Bowman has pointed out that the percentage of water in cotton fibre "varies with different seasons from 1 to 4 per cent. in the new crop, and rather less as the season advances. Above 2 per cent. of moisture, however, seems to be an excessive quantity even in a new crop cotton, and when more than this is present it is either the result of a wet season and the cotton has been packed before drying, or else it has been artificially added."
About one fifth of the whole plant by weight consists of the seed, and an analysis of this shows them to be composed of water, ash, nitrogen, phosphoric acid, potash, soda, lime, magnesia, sulphuric acid, ferric oxide, chlorine, and insoluble matter.
As a commercial product seeds are exceedingly valuable, and yield the following substances:—oil, meal, hulls, and linters. When the hulls are ground they receive the name of cotton seed bran. The inside of the seed, when the hull has been removed, is often called the kernel and is sometimes also designated peeled seed, hulled seed, and meats. It is this kernel seed which, when properly treated, yields large supplies of oil and meal.
CHAPTER II.
COTTON-PLANT DISEASES AND PESTS.
There are several classes of agents all of which act injuriously more or less on the Cotton plant.
1. Climatic changes, including hygrometric variations of the atmosphere, and extremes of heat and cold.
2. Insect pests.
3. Physiological diseases of the plant.
4. Blights caused by fungi.
It has been pointed out in the early pages of this story, how very sensible to changes of heat and cold, the Cotton plant is, especially in the early growing period. When the plant has just risen above the ground, and is beginning to spread its roots, too great an amount of heat would be fatal to its further growth.
Instances could be given where very serious decreases in the production of cotton in the States especially have taken place, due entirely to unusually high temperatures which obtained during the early growing period of the Cotton plant.
Extremes of frost are likewise fatal to the growth of the young plant. By the beginning of April, frosts have as a rule disappeared, and no further fear need be felt on that account, though if the end of winter has been abnormally warm, and the young plants have been making leaf too quickly, it will be readily seen how fatal a sharp frost or two must be to the young and tender plant. There are cases, however, when a frost is beneficial.
Then again, while rain is needed in fair quantity, too much of it is followed by rot and myriads of pests. If the planter desires anything at all when his crop is ripe, it is fine weather in which to gather his harvest.
Frequently large quantities of cotton are left on the plantations, because it is too wet to gather it. This happened a few years ago to an unusual extent, when a vast quantity of cotton had to be left upon the fields.
Of all the injurious agents most dreaded in the cotton-growing districts of the globe, none are so widely spread or so disastrous as "insect pests."
They attack different parts of the plant during its growth, and when the bolls are formed they commit great havoc among these by boring through and completely ruining the immature fibre. Then again, while the plant is young, they may attack the most tender portion of the plant, viz., the new and young leaves found at or near the top. This they soon clear and make their way as caterpillars down the plant, and they frequently clear it as though the leaves had been plucked off.
So completely do they do their work that it has been calculated in certain years the loss on this account alone cannot have been far short in America of 3-1/2 million pounds in one year.
Of the chief forms of insect pests, two specially stand out into prominence, both of which belong to the moth tribe of insects, viz., Alethia argillacea or Cotton Caterpillar, and the Heliothis armiger or Cotton Boll-Caterpillar.
The operations of the former are mostly confined to devastating the leaves and buds, while the latter confines its special attention to the bolls which, were they allowed to ripen, would burst with cotton.
The eggs of the former, too, are laid on the under side of the upper leaves and vast numbers are deposited. The moth flies by night, and the eggs laid are extremely difficult to discover—indeed it takes an expert to quickly find them.
Usually, about midsummer, the eggs are hatched in three or four days and then comes the period for spoliation.
All that is tender is assimilated, usually the under side of the young tender leaves found at the top of the plant.
During this stage of its existence the caterpillar moults five times and the larva period varies somewhat according to the weather from one to three weeks.
The chrysalis or pupa state covers from one week to four, and at last emerges as a beautiful olive gray moth with a purplish lustre.
In about four days the female commences to lay eggs very rapidly and will lay sometimes as many as six hundred during its life. No wonder, then, with several generations during a season and vast numbers of moths, that untold damages can be wrought by these particular insects in a single season.
A number of remedies has been successfully applied in the direction of spraying various chemical solutions, and in sowing plants which have had the direct effect of reducing the spread of this terrible pest. Its method of working can be seen on referring to Fig. 4.
Now the Boll-Caterpillar, though it lives much in the same way as the Alethia, has a very different method of procedure so far as its destructive habits are concerned.
And its fields and pastures, too, are by no means confined to one continent, or to one kind of plant, for it attacks both the tomato and corn plants. According to Dr. Howard, "It feeds upon peas, beans, tobacco, pumpkin, squash, okra, and a number of garden flowering plants, such as cultivated geranium, gladiolus, mignonette, as well as a number of wild plants." As the name indicates, the Boll-Caterpillar makes the boll its happy hunting-ground. The eggs are laid in the same way by the parent moth as the Cotton Caterpillar or Alethia, and when hatched the young powerfully jawed caterpillar makes its way to the newly-formed boll, and applying itself vigorously, very soon gains an entrance. Here it rests for a time, eating away at the best it can find. It ultimately emerges and is transformed into the pupa, taking up its quarters in the ground, until the next change takes place, when in a week or two's time it appears as a moth much the same in size as its cousin the Alethia, but coloured ochre yellow to dull olive-green and being more varied in its markings. It will lay during one season about 500 eggs.
Many remedies have been applied for the extirpation of this particular insect, but these only seem to have met with partial success. It will readily be seen how much more difficult this pest is to deal with than the preceding one. Living as it does in the boll and in the ground for a great part of its existence, it will be exceedingly difficult to get at.
In Mexico what is known as the Cotton-Boll Weevil (Anthonomus grundis) appears to do great mischief to the Cotton plant. It does most damage during the larvae stage, eating up the tender portions of the boll while in residence here. When matured it is only a little under half an inch in length.
Many other insects act injuriously upon the Cotton plant, but the following may be taken as the chief: Cotton Cutworm (Feltia malefida); Cotton lice (Aphis gossypii). Among the lepidoptera may be mentioned, Cocaecia rosaceana, or "Leaf-roller," so called from its habit of curiously rolling the leaves of the Cotton plant and then feeding inside the roll. Then grasshoppers and locusts occasionally do some damage, as well as a beetle named Ataxia crypta, which is noted for attacking the stalks of the Cotton plants, but it should be pointed out this beetle does not prey upon healthy and vigorous plants at all.
Scores of other insects could be mentioned as injurious, though some of them do but very slight damage indeed to the Cotton plant.
It does appear, however, from long years of experiment and observations, that little damage needs to be feared if the plants, while growing, and during the formation of the boll, can be carefully watched and guarded. The plants when matured are better able to withstand the onslaughts which these predaceous insects make upon them.
Then again, there are large numbers of physiological diseases of the cotton due to inherent weakness of the plant or failure of assimilative processes.
And lastly, vast numbers of fungi, too numerous to mention here, work serious injury to leaf, flower and boll in certain seasons of the year.
CHAPTER III.
CULTIVATION OF THE COTTON PLANT IN DIFFERENT COUNTRIES.
From what has already been said, it will be quite clear that the Cotton plant will only successfully thrive in those regions on the earth's surface where there are suitable temperature and soil, and a proper and adequate supply of moisture both in the atmosphere and soil. When the 45th parallel of North Latitude is reached, the plant ceases to grow except under glass or in exceptionally well favoured and temperate districts. Below the Equator the southern limit is the 35th parallel.
With a model of the globe before him, the reader will see, if he mark the two lines already named, what a small belt the "Cotton-growing zone" is, compared with the rest of the globe, and yet in 1901 it is estimated that no fewer than 10,486,000 bales of 500 lbs. net average each were produced in the United States alone, 695,000 came from the cotton fields of India, from Egypt 1,224,000, an increase of 600,000 bales in ten years. This vast quantity does not include what was produced in other countries, which we know in the aggregate was very considerable.
American Cultivation of the Cotton Plant.—Perhaps no country illustrates the fact so well as does the United States, that the variations in the quality of cotton are very largely—it may be said almost entirely—due to distance from sea board, height above sea level and difference of soil.
The surface geology of the Southern United States as a whole, is of a most diversified character, and the following States in which cotton is produced, in many cases show a similar variation.
North Carolina. Tennessee. South Carolina. Alabama. Georgia. Mississippi. Florida. Louisiana. Arkansas. Texas.
Perhaps Texas shows the greatest number of distinct soil areas, viz., eight. Height above the sea level has also a considerable influence upon the plants cultivated, and only the hardier and more robust types are to be found on the more elevated lands. At the beginning of the nineteenth century South Carolina produced more cotton than any other State. Fifty years later, Alabama was to the front. Ten years later, Mississippi led the way, and in 1901 Texas occupied the premier position with 3,526,649 bales, followed in order by Georgia and Mississippi.
The following table from Bulletin 100 of the Bureau of the Census, Department of Commerce and Labor, gives the acreage devoted to cultivation of cotton in 1908 as follows:
Alabama 3,591,000 acres. Arkansas 2,296,000 " Florida 265,000 " Georgia 4,848,000 " Louisiana 1,550,000 " Mississippi 3,395,000 " Missouri 87,000 " North Carolina 1,458,000 " Oklahoma 2,311,000 " South Carolina 2,545,000 " Tennessee 754,000 " Texas 9,316,000 " Virginia 28,000 " ————— 32,444,000 "
The figure for Missouri includes other cotton-producing localities not named.
Before dealing with the actual cultivation of cotton, as carried on in the States, it will be well to briefly name the kind of soils which are met with in this cotton area. Generally speaking, soils are divided into the following classes:—
Clayey soils. Clayey loam soils. Loamy soils. Sandy loam soils. Sandy soils.
This classification is determined by the relative percentage of sand and clay.
In the States we have all these types, and in some districts they lie within easy reach of each other. It should be pointed out that sufficient and uniform heat and humidity are essential to the production of good cotton crops, and as the sandy soils are of an open character, it is plain that moisture will readily pass from these, while the heavy clays act just in the opposite direction, viz., prevent the uniform evaporation of the moisture within them; hence, as a rule, clayey lands are moist and damp, and it has been found from observation that on lands of this class, a good deal of wood and leaf are produced, and but little fruit relatively. A matter therefore which must not be lost sight of, is that a suitable texture should be found, or, in other words, the amount of sand and clay in the soils should be in the right proportion. Of course, however suitable a soil may be, if the climatic conditions are adverse, only failure can result. Given good land, properly drained and a suitable temperature, together with an uniform supply of moisture, heavy crops may be expected. Sudden changes in the temperature, and variations in the amount of moisture, certainly act deleteriously upon the plant, especially during the period in which the young one is growing. There is a great difference between a wet soil and a moist one, and there is perhaps nothing so much dreaded by the planters as a sodden soil. Up to the end of July the soil should be continuously and uniformly moist, and it would appear that, provided this condition is satisfied, there is every likelihood of a heavy crop resulting, if the temperature has been anything like suitable. Looked at from every point of view, therefore, the best and safest soil in which to grow cotton is a deep loam where there is every probability of the necessary conditions being fulfilled.
As compared with sixty years ago the present methods of cultivation show very great differences. Most of us are acquainted with the conditions of labour which existed at that time. Mrs. H. Beecher Stowe, in her pathetic and life-like story, "Uncle Tom's Cabin," has given us such a glimpse into slave life that she has placed us all under lasting obligations to her. Happily all that has gone and the slave, as such, is now known no more in America. Three causes are said to have done more to change the methods of American cotton cultivation than anything else, viz.:—
The Civil War. The abolition of slavery. Introduction of artificial fertilisers.
There are those who affirm to-day that the last-named has been the most potent factor of the three.
In many cases, previous to the war, crop after crop was grown upon the same land without any thought of returning those elements, in the form of manure, to the earth, which it so much required. But immediately after the conclusion of the war, the conditions of labour were changed and it became a matter of absolute necessity to find something which would give life to the land, hence the introduction of fertilisers. It is stated on the authority of Dr. White of Georgia, that it would be "difficult to conceive how cotton culture could have been continued or sustained but for the use of such manures."
In a work of this kind it is impossible to describe in detail the various methods of cultivation adopted in the several cotton States, but the following will give a fair idea of what actually takes place on a large cotton plantation, assuming that the land is well drained. It should be said here draining has not received that attention which it ought to have done, and many of the failures put down to other causes are now known to have been due entirely to bad drainage. As an alternative to proper drainage, the practice of raising the Cotton plant beds and cultivating them to greater depth, has been followed. Most of the planters are too poor to drain properly, and so adopt the banking method, though in the long run this is the more expensive of the two.
Let us assume that the cotton crop has all been gathered. We have an immense quantity of old cotton stalks which need removing. This is usually done before February. As a rule, the litter is gathered into heaps and burned. Ploughing and harrowing next follow, and ridges are formed which in the elevated districts are not quite so far apart as in the low-lying areas. We can see that in the latter districts the plants will be much more prolific and grow to a better state of perfection, hence more room must be allowed for them. These ridges lie, in some cases, 3 feet apart and in others 4 and 5.
Especially when manures or fertilisers have been used, bedding up is generally adopted.
As is to be expected in a country like America, the very best and most approved methods of cultivation are followed, hence the old system of sowing seed by hand is discarded, and seed-planting machines are now coming into general use. The distance apart which the seeds (about five or six in one hole) should be set, is still a moot question, but it is generally admitted to be unsafe to plant at greater distances than 12 inches. When sown, a light covering is put over, and in a few days—about twelve generally—the tiny plants make their appearance. Two or three days after, another leaf is seen, and it may be said that the real and anxious work of the cultivator now begins. In the Carolina districts this will happen about the end of April. The planting in the more southern States will take place earlier. What has next to be done is very particular work, viz., cutting down and thinning the plants, which, if allowed to grow, would simply choke one another. Here and there at suitable distances, groups of plants in the same row are selected as "stands" or groups of plants from which will be selected the best plant, which is allowed to go forward in its growth; all the rest being chopped out or weeded out.
Banking up or bedding up is the next process, and this is done running the plough in the spaces between the ridges or practically over the old cotton bed of the preceding season. This will improve the ventilating power of the bed considerably and prevent somewhat the logging of the soil, which is extremely undesirable. The plough is immediately followed by the field labourers, whose work is now to draw the loose soil round the Cotton plants. This last process of "hauling" completes the labourers' work for a time, and is done for the purpose of keeping the plant erect and preventing it from falling down. This hauling process is repeated until July, when only one plant is left out of the five or six which were planted originally. After four haulings, which are completed as a rule by the end of July, the productive processes may be said to be completed. If the weather has been favourable and the soil kept fairly moist, a good crop may be fully anticipated. What the planters like to see during the growing period is a summer in which the sun shines every day, accompanied by those frequent and gentle showers which clean the plant and give the necessary humidity to the atmosphere and soil. Two things are dreaded by the planter—excessive heats and abnormal showers. The bloom appears about the middle of June and a couple of months after this the plants are ready for picking. This operation usually is carried on from the beginning of September or end of August right on into November, sometimes through this month into December. Here are given a few particulars which have been collected by Shepperson bearing on this particular subject.
+ -+ -+ + -+ + -+ Usual Usual Usual date to Usual date date to Usual date to date to begin to begin finish begin Picking. finish STATES Preparing Planting. Planting. Picking. the Land. + -+ -+ + -+ + -+ N. Carolina Feb. 25 April 15 May 10 Sep. 1 Dec. 10 S. Carolina Mar. 5 April 15 May 7 Aug. 15 to Sep. 1 Dec. 1 Georgia Feb. 1 April 10 May 1 Aug. 15 to 20 Dec. 1 Florida Jan. 20 April 1 May 1 Aug. 10 Dec. 1 Alabama Feb. 1 April 5 May 10 Aug. 10 to 20 Dec. 15 Mississippi Feb. 1 April 5 May 10 Aug. 10 to 20 Dec. 15 Louisiana Feb. 1 April 1 May 10 Aug. 1 to 15 Dec. 15 Texas Jan. 15 March 15 May 10 Aug. 1 Dec. 20 Arkansas Feb. 15 April 15 May 15 Aug. 15 to 20 Jan. 15 Tennessee Mar. 1 April 15 May 15 Sep. 1 to 10 Jan. 15 + -+ -+ + -+ + -+
Other Cotton-producing Countries in America.—In addition to the States, which have already been named, there are other cotton-producing countries in the Western Hemisphere, among which are the following:—
Brazil. Mexico. West Indies. Peru and the South Sea Islands.
Cultivation of Cotton in Brazil.—From a very remote period, cotton has been cultivated in Brazil. Early in the sixteenth century historians refer to the uses to which cotton was put at that time. Seguro, in his work describing the customs of the ancient people who lived in the Amazon valleys, says that the arrows used in connection with their blowguns were covered with cotton. It is probable that, before the dawn of the eighteenth century, the cultivation of cotton was practised more or less throughout the country. Up to thirty years ago, it looked as though the cotton-growing industry in Brazil was likely to be an increasing and profitable business. Owing, however, to many causes, the trade has not grown as was to have been expected.
Among the chief of these causes are:—
1. Laxity of method in cultivating. 2. Poor means of transmission. 3. Severe competition by the United States. 4. Disturbed condition of the country.
All these have helped to keep down an industry which at one time bade fair to be a source of great income to the country.
Tree Cotton and Herbaceous Cotton are both cultivated in Brazil. The best kinds of Sea Islands have been tried, but have not succeeded.
Compared with the United States, the methods of cultivation pursued in Brazil are exceedingly primitive and irregular. No such thing as ploughing or preparing of the soil is adopted.
The only preparation seems to be to rid the land of cotton stumps, and this is done in a somewhat careless and indifferent manner. It would seem that as little labour as possible is expended upon the land in preparing it for the reception of seed. Hilaire's aphorism—"Nothing in this country is less expensive, or more productive, than cotton culture"—would seem, when the facts of the whole case are known, to be perfectly warranted so far as Brazil is concerned. Certainly, from a climatic point of view, this country is exceptionally well favoured, an equable and suitable temperature together with an adequate supply of earth and air, moisture and rich alluvial soils, a long dry season for picking extending over many weeks—all point to an ideal cotton-growing area. In fact, there is no reason why a crop of at least 40,000,000 bales should not be obtained annually in Brazil, if needed. At present, only about one three-hundredth part of this is grown. The cotton-growing centres are Minas Geraes, Bahia, Fernando de Noronha, Rio Janeiro, Sao Paulo.
Cotton Cultivation in Mexico.—The cultivation of cotton has for many centuries been carried on in Mexico. Much the same drawbacks exist here as in Brazil, viz., lack of labour, poor railway system, high rates for transmission, and indifferent methods employed in cultivating.
Mexico enjoys a splendid geographical position and would prove, if the business-like habits and methods obtained as in case of the States, one of the most serious competitors of its adjacent Northern neighbour.
The best cotton is produced in the State of Guerrero on the Eastern side, though the greater part—about one half—of the Mexican crop is grown in Laguna district, which lies in the Coahuila country. There are three distinct areas of production in Mexico, viz., along the Eastern coast, along the Western coast, and on the Central tableland. In the Western area irrigation is resorted to.
In the year 1898, 100,000,000 pounds of cotton were grown, though all or nearly all of it was used at home. Within the last twenty years many mills have been erected in this country, and this will account for the large quantity of cotton consumed at home. The poorest Mexican cotton is produced in Chiapas. Acapulco, near the mouth of the Grande del Norte River, is the chief Mexican cotton port on the Eastern coast.
Cotton-growing in Peru.—It would be a difficult matter to fix a time when cotton was first grown in Peru. Pizarro, who conquered this country early in the sixteenth century, found that the natives were fully engaged in the growing and spinning of cotton. Dr. Dabney, Assistant Secretary of the U.S.A. Agricultural Department, states that he has seen a cloth made of cotton recently taken from one of the Peruvian mummies which must be many, many centuries old. There is not the slightest doubt that the Cotton plant is indigenous to Peru.
Thirty-five years ago Liverpool received no less than 300,000 pounds weight of cotton from Peru, and three years later over 4,000,000 pounds. During the last decade of the century it exceeded 6,000,000 pounds to England alone. Two kinds of Peruvian cotton are grown—smooth and rough. This latter is a rough, strong fibre, and is exceptionally well adapted for mixing with wool in the manufacture of hosiery, and a greater part of this cotton coming in England is used in the hosiery trade. The plant from which it is produced is a perennial, and for six or seven years is said to give two crops a year. Owing to the peculiarly favourable climate of Peru and the suitability of the soil, it is exceedingly improbable that any strong competitor will come to divert the Peruvian trade, so that for some time yet we may look to this country supplying the hosiery trade with rough Peruvian cotton. The importations of Peruvian cotton into the United States for 1894-95 were 24,000 bales; for 1895-96, 24,603 bales; for 1896-97, 16,604 bales.
The Cultivation of Cotton in India.—There are other Asiatic cotton fields besides those of India, viz., China, Corea, Japan, the Levant, and Russia in Asia. The term "India" will be used in a somewhat restricted sense in this section, and will cover only that huge triangular-shaped peninsula lying to the south of Thibet in Asia. It is 1800 miles in width and nearly 2000 miles in length. The total area, not including Assam and Burmah, is about 1,300,000 square miles, the native states alone covering 595,000 square miles.
Out of the 28 deg. of North Latitude through which India stretches, no less than 15-1/2 deg. are in the tropics, the remainder being in the Temperate Zone. The climate, owing to a number of circumstances, such as different altitudes and uneven distribution of moisture, is exceedingly varied.
During the months April to September the sun, during the day or some part of it, is overhead. Consequently the heat received will be greater than over the ocean at the south, taking a similar area. A direct cause of this is the starting of winds which receive the name of monsoons. These blow from the S.W., and bring vast quantities of moisture with them. This moisture-laden wind is partially robbed of its load as it strikes the Western Ghats and consequently much moisture is deposited here, giving rise to many valuable rivers which water the Deccan or Central Tableland of India. The Mahanuddy, Godavari, Kristna, and Kauvari are rivers fed by the S.W. monsoon. Then, again, the low-lying lands near the mouth of the Indus, the great desert of Rajputana, the peninsula of Gujerat and the district of Malwa—all allow, by reason of their low-lying nature, the S.W. winds to pass over them laden as they are with vast quantities of moisture. They travel on till they meet the Himalayas, where again they help to swell the volume of the waters in the rivers Ganges and Indus. When the N.E. monsoons blow they do not carry anything like the amount of moisture which the S.W. monsoons do, as their areas of collection are very much more limited. Consequently this part of the year is usually a dry one (viz., from October to March).
Thus it will be seen that the great plain of Southern India is much less watered than the more Northerly portions and consequently is much less fertile. This fact must be borne in mind as the cotton-growing areas are described and indicated.
India, which grows more cotton than any other country in the world (the States excepted), may be said to possess four distinct areas for the production of commercial cotton. They are—
1. Central Tableland or Deccan. 2. Valley of the Ganges. 3. Western India. 4. Southern India.
and the above order shows them also according to their commercial importance.
Central District.—This is a vast plateau bounded on the north by the Vindhya mountains, on the east and west by the Ghats of those names, and on the south by the River Krishna. As is to be expected, the collecting and exporting of the cottons grown in this district are done at Bombay. The finest cottons grown in India are produced in this region.
Four centres stand out prominently in the production of cotton, viz., Dharwar, Hyderabad, Nagpore and Berar. The soils generally in the Deccan are very rich and capable of retaining moisture during the growing term of the plant's life. What are known as the black soils of India are to be found plentifully in this district, and these are exceedingly rich in mineral matter. Nagpore should specially be named, as it is in this province that the finest cotton grown in all India is produced, viz.:—
"Hingunghat Cotton."
"Oomrawattee Cotton" is the name given to a special kind which is produced in the province of Berar. It is sometimes called "Oomras." This district lies in the "Nizam's Dominions" and is watered by several tributaries of the Tapti and Godivari. It possesses a soil which for richness and fertility has no equal in India.
With the exception of Bengal, this district is more plentifully supplied with rivers than any other part of India.
Image: FIG. 5.—An Indian cotton field.
The Dharwar district is noted for its cottons, for two or three reasons. It was in this region that in 1842 New Orleans cotton was planted with a view to its ultimately being cultivated here. As the climate and soil are very similar to some of the districts in the Mississippi valley, it succeeded beyond anticipation. Dharwar lies S. W. of the province of Hyderabad near the sea, and almost touches 15 deg. N. Latitude.
The Valley of the Ganges District cannot be said to grow very good cotton, though it was in this region, at Dacca, that in former days the cotton which was afterward made into the celebrated Dacca muslin was grown.
By far the greater part of the fibre produced in this district comes from two centres: (1) Bundelkhand, which lies 79 deg. E. Long., and 25 deg. N. Latitude (this is very near to Allahabad), and (2) Doab. As was pointed out in describing the monsoons, these two centres suffer by reason of droughts, owing mainly to their geographical position. They are subject also to severe floods, which are certainly against successful cultivation of cotton. The entire crop of the North West Provinces may be said to come from the districts of Doab and Bundelkhand.
Western India District.—The three centres for the production of cotton in the west, may be said to be Peninsula of Guzerat, the Island of Cutch and the Delta district of the Indus named Sind. The whole of these provinces lies in what may be called a dry area, missing, as was shown, much of the S. W. monsoon, which ultimately finds its way across country to the Himalayas. Consequently there will be little rainfall in this area, Sind and Cutch not more than 10 inches, some parts of Guzerat having much more.
This has a very serious effect upon the quality of the cotton produced.
The Surat, Broach and Sind Cottons, all poor types, are all grown in this part of India.
Southern India District.—This lies in the southern part of the Residency of Madras, and east of the province of Travancore. The Nilgiris and Shevaroy Hills are found here, as are also the Cauvery and Vaigai Rivers. The cotton districts best known are Coimbatore and Tinnevelley, both of which are admirably situated and well watered. The Calicut of fame which gave rise to the name Calico is also in this district. Tinnevelley lies almost at the extreme south of India on the Gulf of Manaar opposite to Island of Ceylon. Its cotton is well known, but is of a poor type. As far back as 1847, experiments carried out under the superintendence of Dr. Wright proved that this district was very suitable for the cultivation of American cotton. A fact interesting as well as instructive is given by him to the effect that in the southern part of India the crops universally failed where grown from the native seed, while those grown from American seed realised very fair amounts—better even than were obtained when good crops were got after using Indian seed.
The methods of preparing, planting, and cultivating the Indian Plants are exceedingly antiquated. In but few districts are anything like modern methods practised. Advantage however is taken of the period just preceding the rain monsoon and this differs a little according to the district. Thus in Bengal, Berar, and Broach, May and June are usually taken for scantily preparing the land, and in Madras and Dharwar, August and September. This consists of turning over the soil and burying the old Cotton plants of the previous season which have been allowed to rot. As no fertilisers are used, these roots and branches at best make a very poor substitute. Ploughing, hoeing and other agricultural operations are of the rudest types and oxen are used for almost everything in the way of heavy labour. Farm implements, gearing carts, etc., are all of a style and differ very little from those used centuries ago. The seeds are sown broadcast, and almost everything is done by hand.
The plantations as a rule are much smaller than those in America, running from 5 to 30 acres. On the larger plantations the cotton is cultivated mainly by paid labourers.
The following table, by Shepperson, shows the acreage devoted to cotton of the different states in India:—
Bombay and Sind 5,021,000 acres. Punjaub 1,177,000 " N. W. Provinces 1,424,000 " Bengal 153,000 " Rajputana 549,000 " Central India 503,000 " Berar 2,307,000 " Central Provinces 616,000 " Hyderabad (Nizam's) 2,308,000 " Madras 1,655,000 " Mysore } Assam } 230,000 " Burmah (Lower)} Burmah (Upper)} Ajmere and Meywara 40,000 " ————— 15,983,000 "
Bombay, Kurrachee, Calcutta, Madras, Tuticorin and Cocanada are the chief Indian cotton ports.
Cotton-growing in Russia in Asia.—Lying immediately north of Persia and Afghanistan and south of Khirghiz Steppes lies an immense area much of which is now being cultivated and most of it very fit for the production of cotton. The Sea of Ural has running into it two very large rivers, Amu Daria and the Syr Daria, and it is in the neighbourhood of these two rivers where we find by far the greatest weight of cotton of Turkestan produced.
There are four important areas, viz., Syr Daria, the centre of which is Tashkend; Fergana, which lies between Samarcand and Bokhara; the district of Samarcand itself; and Merv, which stands on the Overland Railway. It appears that many attempts were made to introduce cottons of various types into this locality, but most of the delicate species failed. The Upland of America, however, survived, and has continued to succeed, thanks to the valuable help which the Government gave in the way of instruction and distribution of free seed.
The first Government cotton plantation was commenced at Tashkend, one of the termini of the Transcaspian Railway. Eight years ago there were upwards of a quarter of a million acres devoted to cotton cultivation.
During the American War (that period which quickened all the cotton-growing centres of the Eastern Hemisphere) the production of fibre may be said to have commenced in earnest in Turkestan, and so late ago as 1890 no less than forty-five and a half million pounds of good fibre were grown. Tashkend, it would appear, promises to hold its own, as it is determined to practise the best and most scientific methods in the growth of cotton; in fact, in very few centres outside this district, old and out of date operations are followed. Even in the districts of Fergana and Samarcand, the old wooden plough called a "sokha" is still in use.
Seed, as in the case of India, is mostly sown broadcast, and very little preparing of the land is done. Yet, in spite of these deficiencies, good crops are raised in many districts, capital soil and a most equable climate making up for the shortcomings of the planter. The formation of the Transcaspian Railway cannot but have an important influence upon the cotton-growing industry in Turkestan, running as it does through the very heart of the best land in the country. It should be noted that Bohkara annually produces over 50,000,000 pounds of cotton of the herbaceous type, and Khiva, another district lying still further east of those already mentioned, over 20,000,000 pounds.
Lying between the Caspian Sea and Black Sea, lies another district named Transcaucasia, which yields large supplies of cotton. It has 100,000 acres devoted to cotton, giving over 20,000,000 pounds per annum. North of Kokan, on the river Syr Daria, is a rising cotton district named Khojend, where annually 3,000,000 pounds of cotton of the American type are raised.
When we consider that the quantity of cotton carried by the Transcaspian Railway since 1888 has more than quadrupled, and that in ten years the quantity shipped has been increased from quarter of a million pounds to over 72,000,000 pounds, we can quite appreciate the significance of the statement that before long Russia will be able to grow all her own cotton for the medium and lower numbers of yarns.
Cotton-growing in China, Corea and Japan.—Japan, the land of the chrysanthemum, for many years now has been developing cotton-growing as well as cotton manufacturing. From evidence which the cold type of the Board of Trade gives, Japan bids fair to largely increase her trade with India to the disadvantage of the present suppliers.
Cotton-growing has been practised for some centuries in Japan, but it was not until the seventeenth century that anything like progress could be reported. From that time to the present the growth has been gradually on the increase.
Japan proper consists of the Islands of Niphon, Kiusiu, Shikoku, Yesso, and an immense number of smaller islands. Cotton cultivation is carried on mainly on the first three islands named, and in the following districts:—San Indo, Wakayama, Osaka, Kuantoebene, Hitachi and Suo.
Taken as a whole, the cotton grown in the best areas is good, though much of an inferior kind is produced. The most southerly area of Wakayama in Niphon yields the best cotton of Japan.
The length of the fibre generally is much less than the herbaceous kind. About 10 per cent. of the entire arable land is now under cultivation for cotton. As a rule, methods and processes are of a primitive kind.
Cotton-growing in Corea.—Lying directly to the west of Japan, this vast peninsula has of late years been developing its cotton-growing. Five centuries ago cotton was imported from China, and one sees on every hand the influence of the Celestials. The cultivated plant is of the perennial type, though it is planted annually, the old plants being dug up and burned, the ash being used as a fertiliser. Statistics at present are not to be relied upon, though it is supposed that something like three quarters of a million acres are now under cultivation, giving on the average about 250 pounds of cotton lint. As in the case of Japan very little of this is exported, all of it or nearly so being spun and woven at home on the most primitive of machines.
The chief districts engaged in growing cotton, nearly all of which lie in the southern portion of the peninsula, are Hwang-Hi, Kyeng-Sang, Chel-La, Kyeng Kwi, and Chung Cheog.
Cotton-growing in China.—Owing to the great difficulty of obtaining any reliable statistical information, it is impossible to give anything approaching accuracy as to number of pounds of cotton produced annually, or number of acres devoted to the cultivation of the Cotton plant. This much, however, is known, that for many centuries cotton cultivating has been followed and that there has been within recent years a great increase in the weight of the cotton crop as well as in the acreage. The type of plant most generally cultivated is the herbaceous, and the cotton resulting is only poor in quality. Little or no preparation is made before sowing seed, which is generally done broadcast. As a result there is much overcrowding, and as is inevitable, there is produced a stubby plant with small bolls and much unripe cotton. On the terraces of the hillsides something approaching cultivation is pursued, with the result of a better crop.
Usually twenty weeks intervene between planting and picking, this latter operation being mostly the work of children and women. The old cotton stalks are afterward collected and dried for fuel.
Very few large plantations exist in China, most of them being only a few acres in extent.
But little of the cotton grown at home is exported, most of it being spun and woven by women, though some of the fibre is sent to Japan.
Cultivation of Cotton in Egypt.—It is now over thirty years since Sir Samuel Baker, the great African traveller, wrote these words: "The Nile might be so controlled that the enormous volume of water that now rushes uselessly into the Mediterranean might be led through the deserts, to transform them into cotton fields that would render England independent of America."
The crop for the season 1900-01 was no less than 1,224,000 bales of 500 pounds each. Ten years ago only 868,000 acres were devoted to cotton cultivation as against 1,350,000 acres laid down to-day. Everything, then, points to Sir Samuel Baker's statement becoming an actual fact much sooner than the famous traveller himself anticipated.
Egypt enjoys many advantages over her competitors across the Atlantic. In the first place, she can get almost twice as much cotton from the acre, so productive is the soil. Labour is cheaper, and the plant itself when young is not subject to the devastating frosts so often met with in America.
Egypt is divided into three great areas:—Lower Egypt, which includes the whole of the Delta of the Nile; Upper Egypt; and Nubia. It is in the first-named district where the whole of Egyptian cotton is produced. At the present time immense sums are being spent on irrigation and drainage works, and as these are extended the areas devoted to cotton production will greatly increase.
At the present time five distinct varieties of cotton are cultivated—
Mitafifi. Bamia. Abbasi. Gallini. Ashmouni-Hamouli.
The latter variety was originally known by a different name, Mako Jumel. For a long time Ashmouni cotton was the principal fibre exported, but Mitafifi is now in the front of all the other Egyptian cottons. A noteworthy fact in connection with Ashmouni is, that its cultivation is on the decline.
Sea Islands Gallini—as it was sometimes called—has practically ceased to be cultivated. Of Mitafifi and Bamia fibres, Mr. Handy, U. S. A., says: "The Mitafifi was discovered by a Greek merchant in the village of that name. The seed has a bluish tuft at the extremity, which attracted the merchant's attention, and on planting it he found that it possessed decided advantage over the old Ashmouni. It is more hardy, and yields a greater proportion of lint to the seed. At first from 315 pounds of seed cotton, 112 pounds of lint was secured, and sometimes even more. It is now somewhat deteriorated, and rarely yields so much, averaging about 106 pounds of lint to 315 of seed cotton. The Mitafifi is a richer and darker brown than the Ashmouni. The fibre is long, very strong, and fine to the touch, and is in great demand. In fact, it controls the market.
"Next to Mitafifi, Bamia is perhaps the most extensively cultivated variety in Lower Egypt. It was discovered by a Copt in 1873. The plant is of large size and course growth. It is later and less hardy than Mitafifi, and the fibre is poor as compared with that of Mitafifi and Abbasi, light and brown in colour, and not very strong. In general, it may be said that this variety is inferior to Mitafifi in yield, hardiness and length and strength of fibre."
Other places where Cotton is grown.—In Africa, on the eastern and western coasts, large quantities of cotton are produced. The following countries are specially suitable to the growth of cotton: Soudan, Senegambia, Congo River, Free States, and Liberia. Possibly, when these districts are more opened up to outside trade, and European capital and labour are expended, abundant supplies of cotton fibre will be given.
Cotton is also grown in the East Indies, at Java, Sumatra, and Malay States.
In the West Indies formerly, large supplies were yielded, but owing to the cultivation of other crops that of cotton has steadily declined.
Greece and Turkey both yield cotton which goes by the name of Levant Cotton.
CHAPTER IV.
THE MICROSCOPE AND COTTON FIBRE.
This story would be very incomplete if some reference were not made to the wonderful assistance which has been given to the study of cotton fibre by the microscope. As seen by its help, some striking peculiarities at once make themselves apparent. It is proposed, briefly, in this chapter, to do three things:
1. To describe the construction of a suitable instrument sufficient for a complete examination of fibres in general.
2. To indicate the chief microscopic features of cotton fibres.
3. To show how to exactly measure the lengths and diameters of fibres by means of micrometers.
First, as to the instrument: a good substantial stand is desirable, one that will not readily vibrate. The microscope shown in Fig. 6 is a cheap and commendable form, and good work can be done by this instrument, which is made by Ross, London. The stand carries the body-tube, and at the lower end is placed the objective, so called, because the image of the object (which rests upon the stage as shown) under examination is first focussed by it and conveyed along the body-tube.
The top end of the said tube contains the eye-piece, so named because by its aid the eye is allowed to receive the image duly focussed and enlarged.
As a rule, beginners work with one objective only, generally a one inch.
Image: FIG. 6.—Microscope in position for drawing objects.
A much higher power than this is necessary if the fibre in question is to be seen at its best, and for the purpose of this chapter a quarter inch objective will be used.
Underneath the stage, which is pierced by a circular aperture, is a diaphragm. This regulates the quantity of light which is to be transmitted by means of the silvered reflector shown in the illustration.
As a rule, two reflectors are fixed in the same holder; one a concave mirror, the other a plane one. The former brings the rays of light to a point or focus while the latter simply passes the beam of light along just as it received it, viz., as a parallel beam of light.
In examining fibres the concave mirror will be of most use. An ordinary lamp is usually good enough for the light required, the one figured being very suitable and having a tube-like arrangement of wick. Behind the body-tube are two forms of adjustment, coarse and fine. The latter is worked by means of the milled screw, conical in shape, which is found immediately behind the coarse adjustment. The operator is supposed to have had some slight experience in the manipulation of the microscope. The slide is now placed upon the stage. Fine Sea Islands cotton is mounted in Canada Balsam and protected by a small circular cover glass.
Now rack down the body-tube by means of the coarse adjustment until within 1/16 of an inch of the cover-glass of the slide. Now see that the light from the lamp is fully on the cotton strands. Rack up or down, as the case may be, with the fine adjustment, and a wonderful sight meets the eye, for the cotton viewed through the microscope is altogether unlike what we should expect it to be.
Running completely across the field are a number of strands, varying in thickness, form and natural twist. What is meant by natural twist is very clearly shown in Fig. 7.
Most people have seen india-rubber tubing or piping such as is used in the chemical laboratory or that often found attached to feeding bottles. Take about a foot of this and hold one end firmly. Abstract the air by means of the mouth, and it will be found that immediately the air is taken out the tube collapses. Now if the rubber be variable in thickness, here and there along these lines of least resistance will be found certain twists, and it is the same kind of twists which can be so distinctly seen as the cotton fibre is viewed through the microscope. They are exceedingly irregular in number, on equal lengths of the same single fibre. When they run for some length, and are fairly regular, the edges appear like wavy lines or corrugations. It will now be seen by the reader why these twists are so invaluable in spinning: locking and intertwining with each other, they materially assist the spinner in building up a long and continuous thread.
Image: FIG. 7.—Transverse and longitudinal sections of cotton fibre.
Then, too, are to be seen lying close to the regularly twisted fibres a number of others which are very like ribbons, with here and there an apology for a twist, and further, a careful scrutiny will be rewarded by finding in what is reputedly the best cotton a number of filaments which do not display any twists whatever and are very much like the round tubing referred to a little while ago. Others again are quite flat, without any distinguishing twists whatever. These are said to be the half-ripe and unripe fibres, and give much trouble later on (if worked up with good cotton) to the dyer and spinner.
As the slide containing the cotton is moved laterally, it will be seen that this twisting of the fibre is continued for almost the whole length, and as many as 300 twists have been counted on a single filament. In some, the fibre tapers slightly, becoming more and more cylindrical as the end most remote from the seed is approached, until it is quite solid. These stiff ends soon disappear after the cotton has been treated in the early processes of manufacture. Thus there may be found in almost every sample of cotton what are called ripe, half-ripe and unripe cotton. The last-named kind result from—
1. Gathering the crop before the boll is properly ripened and matured.
2. Bad seasons; too much moisture and too little heat.
Then again in the same boll all fibres do not ripen together just as all apples on the same tree do not ripen together.
Immature or unripe cotton cannot be dyed, and when small white specks are seen in any dyed fabric they are often due to the fact that unripe cotton has been used in the manufacture of the cloth.
Measurement of the Cotton Fibre.—This is not at all a difficult matter, and the ordinary student may, by means of very simple and inexpensive apparatus, obtain fairly satisfactory results in the measurement of fibres.
There is a choice of one of three methods, viz.:—
1. By having the mechanical stage so arranged that the slightest displacement either to the left or right can be measured, and having the eye-piece so marked (generally a hair stretched across it) that when an object is to be measured, one side of it is made to coincide with this central line and the stage rack is worked left or right until the opposite side of the object is brought coincident with the central line again; the amount of displacement can then be readily obtained on referring to the graduated stage.
2. By having a stage micrometer and camera lucida.
3. By having two micrometers, a stage micrometer and eye-piece micrometer.
This latter method is certainly the least expensive, and for all practical purposes can be safely recommended.
A stage micrometer consists of a slip of glass 3" x 1" on which are marked divisions of an inch, usually 1/100ths and 1/1000ths. As a rule these markings are protected by means of a small cover-glass.
Eye-piece micrometers vary much in form, size and value, but the one which is here described is of the simplest type. It consists of two circular pieces of glass carefully cemented together. On one of the inner surfaces are marked usually the 1/100ths divisions of an inch. In some 1/200ths are marked. If the top lense of the eye-piece be unscrewed, a diaphragm will be found on which the eye-piece micrometer will easily rest. Screw on the top lense again and, generally, the eye-piece will be ready for use. If the micrometer is not properly in focus after a few trials, it may easily be made right. In order, then, to measure the diameter of a single fibre of Sea Islands cotton, fit in the quarter inch objective and place the stage micrometer in position on the stage. First, focus the fine lines which are plainly to be seen, and remember the lines which are farthest apart are 1/100th of an inch; the others 1/1000th of an inch.
As a rule, these lines run from N. to S. of the field; in other words, from top to bottom across the circles of light. Now look at the divisions in the eye-piece micrometer, which are 1/100th of an inch apart.
It will be found often that an exact number of these divisions fill up one of the 1/100th divisions of the stage micrometer markings. If an exact number are not found, the draw-tube at the top end of the body-tube should be withdrawn until an exact number is found to lie within two lines of the lower micrometer.
Suppose twenty-two of the spaces on the eye-piece micrometer just cover one of the divisions (1/100th of an inch) on the stage micrometer. Then it is clear that each division of the former represents 1/100 x 1/22 of an inch, or 1/2200th of an inch. For every fresh objective used, a fresh estimation of eye-piece and stage micrometer ratio is necessary. Having now got in the eye-piece micrometer a unit of measurement, it becomes a comparatively easy matter to measure the fibre.
Remove the stage-micrometer and put a slide of Sea Islands cotton in its place. Focus the fibre and observe the number of divisions or parts of a division covered by any particular fibre, and its measurement is at once known. Thus if a single filament covers two of the divisions then it is 2/2200th of an inch in diameter, or 1/1100th of an inch. Exactly the same method is adopted if it is desired to measure the diameters of sections of the same fibres. |
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