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The Home Medical Library
By
KENELM WINSLOW, B.A.S., M.D.
Formerly Assistant Professor Comparative Therapeutics, Harvard University; Late Surgeon to the Newton Hospital; Fellow of the Massachusetts Medical Society, etc.
With the Cooperation of Many Medical Advising Editors and Special Contributors
IN SIX VOLUMES
First Aid :: Family Medicines :: Nose, Throat, Lungs, Eye, and Ear :: Stomach and Bowels :: Tumors and Skin Diseases :: Rheumatism :: Germ Diseases Nervous Diseases :: Insanity :: Sexual Hygiene Woman and Child :: Heart, Blood, and Digestion Personal Hygiene :: Indoor Exercise Diet and Conduct for Long Life :: Practical Kitchen Science :: Nervousness and Outdoor Life :: Nurse and Patient Camping Comfort :: Sanitation of the Household :: Pure Water Supply :: Pure Food Stable and Kennel
NEW YORK
The Review of Reviews Company
1907
Medical Advising Editors
Managing Editor
ALBERT WARREN FERRIS, A.M., M.D.
Former Assistant in Neurology, Columbia University; Former Chairman, Section on Neurology and Psychiatry, New York Academy of Medicine; Assistant in Medicine, University and Bellevue Hospital Medical College; Medical Editor, New International Encyclopedia.
Nervous Diseases
CHARLES E. ATWOOD, M.D.
Assistant in Neurology, Columbia University; Former Physician, Utica State Hospital and Bloomingdale Hospital for Insane Patients; Former Clinical Assistant to Sir William Gowers, National Hospital, London.
Pregnancy
RUSSELL BELLAMY, M.D.
Assistant in Obstetrics and Gynecology, Cornell University Medical College Dispensary; Captain and Assistant Surgeon (in charge), Squadron A, New York Cavalry; Assistant in Surgery, New York Polyclinic.
Germ Diseases
HERMANN MICHAEL BIGGS, M.D.
General Medical Officer and Director of Bacteriological Laboratories, New York City Department of Health; Professor of Clinical Medicine in University and Bellevue Hospital Medical College; Visiting Physician to Bellevue, St. Vincent's, Willard Parker, and Riverside Hospitals.
The Eye and Ear
J. HERBERT CLAIBORNE, M.D.
Clinical Instructor in Ophthalmology, Cornell University Medical College; Former Adjunct Professor of Ophthalmology, New York Polyclinic; Former Instructor in Ophthalmology in Columbia University; Surgeon, New Amsterdam Eye and Ear Hospital.
Sanitation
THOMAS DARLINGTON, M.D.
Health Commissioner of New York City; Former President Medical Board, New York Foundling Hospital; Consulting Physician, French Hospital; Attending Physician, St. John's Riverside Hospital, Yonkers; Surgeon to New Croton Aqueduct and other Public Works, to Copper Queen Consolidated Mining Company of Arizona, and Arizona and Southeastern Railroad Hospital; Author of Medical and Climatological Works.
Menstruation
AUSTIN FLINT, JR., M.D.
Professor of Obstetrics and Clinical Gynecology, New York University and Bellevue Hospital Medical College; Visiting Physician, Bellevue Hospital; Consulting Obstetrician, New York Maternity Hospital; Attending Physician, Hospital for Ruptured and Crippled, Manhattan Maternity and Emergency Hospitals.
Heart and Blood
JOHN BESSNER HUBER, A.M., M.D.
Assistant in Medicine, University and Bellevue Hospital Medical College; Visiting Physician to St. Joseph's Home for Consumptives; Author of "Consumption: Its Relation to Man and His Civilization; Its Prevention and Cure."
Skin Diseases
JAMES C. JOHNSTON, A.B., M.D.
Instructor in Pathology and Chief of Clinic, Department of Dermatology, Cornell University Medical College.
Diseases of Children
CHARLES GILMORE KERLEY, M.D.
Professor of Pediatrics, New York Polyclinic Medical School and Hospital; Attending Physician, New York Infant Asylum, Children's Department of Sydenham Hospital, and Babies' Hospital, N. Y.; Consulting Physician, Home for Crippled Children.
Bites and Stings
GEORGE GIBIER RAMBAUD, M.D.
President, New York Pasteur Institute.
Headache
ALONZO D. ROCKWELL, A.M., M.D.
Former Professor Electro-Therapeutics and Neurology at New York Post-Graduate Medical School; Neurologist and Electro-Therapeutist to the Flushing Hospital; Former Electro-Therapeutist to the Woman's Hospital in the State of New York; Author of Works on Medical and Surgical Uses of Electricity, Nervous Exhaustion (Neurasthenia), etc.
Poisons
E. ELLSWORTH SMITH, M.D.
Pathologist, St. John's Hospital, Yonkers; Somerset Hospital, Somerville, N. J.; Trinity Hospital, St. Bartholomew's Clinic, and the New York West Side German Dispensary.
Catarrh
SAMUEL WOOD THURBER, M.D.
Chief of Clinic and Instructor in Laryngology, Columbia University; Laryngologist to the Orphan's Home and Hospital.
Care of Infants
HERBERT B. WILCOX, M.D.
Assistant in Diseases of Children, Columbia University.
Special Contributors
Food Adulteration
S. JOSEPHINE BAKER, M.D.
Medical Inspector, New York City Department of Health.
Pure Water Supply
WILLIAM PAUL GERHARD, C.E.
Consulting Engineer for Sanitary Works; Member of American Public Health Association; Member, American Society Mechanical Engineers; Corresponding Member of American Institute of Architects, etc.; Author of "House Drainage," etc.
Care of Food
JANET MCKENZIE HILL
Editor, Boston Cooking School Magazine.
Nerves and Outdoor Life
S. WEIR MITCHELL, M.D., LL.D.
LL.D. (Harvard, Edinburgh, Princeton); Former President, Philadelphia College of Physicians; Member, National Academy of Sciences, Association of American Physicians, etc.; Author of essays: "Injuries to Nerves," "Doctor and Patient," "Fat and Blood," etc.; of scientific works: "Researches Upon the Venom of the Rattlesnake," etc.; of novels: "Hugh Wynne," "Characteristics," "Constance Trescott," "The Adventures of Francois," etc.
Sanitation
GEORGE M. PRICE, M.D.
Former Medical Sanitary Inspector, Department of Health, New York City; Inspector, New York Sanitary Aid Society of the 10th Ward, 1885; Manager, Model Tenement-houses of the New York Tenement-house Building Co., 1888; Inspector, New York State Tenement-house Commission, 1895; Author of "Tenement-house Inspection," "Handbook on Sanitation," etc.
Indoor Exercise
DUDLEY ALLEN SARGENT, M.D.
Director of Hemenway Gymnasium, Harvard University; Former President, American Physical Culture Society; Director, Normal School of Physical Training, Cambridge, Mass.; President, American Association for Promotion of Physical Education; Author of "Universal Test for Strength," "Health, Strength and Power," etc.
Long Life
SIR HENRY THOMPSON, Bart., F.R.C.S., M.B. (Lond.)
Surgeon Extraordinary to His Majesty the King of the Belgians; Consulting Surgeon to University College Hospital, London; Emeritus Professor of Clinical Surgery to University College, London, etc.
Camp Comfort
STEWART EDWARD WHITE
Author of "The Forest," "The Mountains," "The Silent Places," "The Blazed Trail," etc.
[Illustration: WALTER REED.
In the year 1900, Major Walter Reed, a surgeon in the United States Army, demonstrated, by experiments conducted in Cuba, that a mosquito of a single species, Stegomyia fasciata, which has sucked the blood of a yellow-fever patient may transmit the disease by biting another person, but not until about twelve days have elapsed. He also proved, as described in Volume I, Part II, that the malady is not contagious. "With the exception of the discovery of anaesthesia," said Professor Welch, of Johns Hopkins University, "Dr. Reed's researches are the most valuable contributions to science ever made in this country." General Leonard Wood declared the discovery to be the "greatest medical work of modern times," which, in the words of President Roosevelt, "renders mankind his debtor." Major Reed died November 23, 1902.]
The Home Medical Library
VOLUME V :: SANITATION
Edited by
THOMAS DARLINGTON, M.D.
Health Commissioner of New York City; Former President Medical Board, New York Foundling Hospital, etc.; Author of Medical and Climatological Works
WATER SUPPLY AND PURIFICATION
By WILLIAM PAUL GERHARD, C.E.
Consulting Engineer for Sanitary Works; Author of "House Drainage," "Sanitary Engineering," "Household Wastes," etc.
PURE FOOD FOR THE HOUSEKEEPER
By S. JOSEPHINE BAKER, M.D.
Medical Inspector, New York City Department of Health
THE HOUSE AND GROUNDS
By GEORGE M. PRICE, M.D.
Former Medical Sanitary Inspector, Department of Health, New York City; Author of "Tenement-House Inspection," "Handbook on Sanitation," etc.
NEW YORK
The Review of Reviews Company
1907
Copyright, 1907, by
THE REVIEW OF REVIEWS COMPANY
THE TROW PRESS, NEW YORK
Contents
PART I
CHAPTER PAGE
I. COUNTRY SOURCES OF WATER SUPPLY 19
Relation of Water to Health—Collection of Rain Water—Cisterns—Springs—Various Kinds of Wells—Laws Regulating Supply.
II. APPLIANCES FOR DISTRIBUTING WATER 39
Pumping Machines—The Hydraulic Ram—Use of Windmills—Engines—Steam and Electric Pumps—Reservoirs and Tanks—Appliances for Country Houses.
III. PURIFYING WATER BY COPPER SULPHATE 52
Clear Water Often Dangerous—Pollution Due to Plants—Copper Sulphate Method—Directions for the Copper Cure.
IV. RIDDING STAGNANT WATER OF MOSQUITOES 70
Malaria Due to Mosquitoes—Cause of Yellow Fever—Effect of a Mosquito Bite—Destruction of Larvae—Best Preventive Measures—Use of Kerosene.
PART II
I. HOW TO DETECT FOOD ADULTERATION 87
Definition of Adulteration—Food Laws—Permissible Adulterants—How to Select Pure Food—Chemical Tests.
II. MUSHROOM POISONING 112
Symptoms and Treatment—Coffee and Atropine the Best Antidotes—How to Tell the Edible Kind—"Horse," "Fairy-ring," and Other Varieties—Poisonous Species.
PART III
I. SOIL AND SITES 131
Constituents of the Soil—Influence on Health—Improving Defective Soil—Street Paving and Tree Planting—Proper Construction of Houses—Subsoil Drainage.
II. VENTILATION 146
What is Meant by Ventilation—Quantity of Air Required—Natural Agents of Ventilation—Special Appliances.
III. WARMING 160
Various Methods—Materials of Combustion—Chimneys—Fireplaces and Grates—Stoves—Hot-air Warming—Hot-water Systems—Principles of Steam Heating.
IV. DISPOSAL OF SEWAGE 170
Refuse and Garbage—Discharge into Waters—Cremation—Precipitation—Intermittent Filtration—Immediate Disposal, etc.
V. SEWERS 182
Definition—Materials Used in Construction—Levels of Trenches—Joints of Pipes—The Fall and Flow of the Contents—Connections—Tide Valves—Sewer Gas.
VI. PLUMBING 189
Purposes and Requisites—Materials Used—Joints and Connections—Construction of Traps—Siphonage and Back Pressure—The Vent-pipe System.
VII. PLUMBING PIPES 206
Construction of House Drains—Fall, Position, and Connection—Main Traps—Extension of Vertical Pipes—Fresh-air Inlets—Soil and Waste Pipes—Branch Pipes, etc.
VIII. PLUMBING FIXTURES 216
Sinks—Washbasins—Washtubs—Bathtubs—Refrigerators, etc.—Safes and Wastes—Pan, Valve, and Hopper Closets—Flush Tanks—Yard Closets—Drains.
IX. DEFECTS IN PLUMBING 231
Poor Work—Improper Conditions—How to Test Traps, Joints, and Connections—Detect Sewer Gas—Water-pressure, Smoke, and Scent Tests—Special Appliances.
X. INFECTION AND DISINFECTION 238
Physical and Chemical Disinfectants—Use of Sulphur Dioxide—Formaldehyde—Hydrocyanic Acid—Chlorine—Carbolic Acid—Bichloride of Mercury—Formalin—Potassium Permanganate, etc.
XI. COST OF CONVEYED HEATING SYSTEMS 254
Cost of Hot-air Systems—Cast-iron Hot-water Heater—Advantages and Disadvantages—Cost for a Ten-room House—Steam Heating—Cost of Equipment.
The Editor's Preface
The character and scope of this volume render it a most useful book for the home maker. The question of sanitation is one that closely affects the life of each individual, and many of its aspects are treated here in a lucid and comprehensive manner. Designed for wide distribution, these articles have been written to meet the needs of the dweller in the more densely populated communities, as well as those living in the less thickly settled portion of the country.
In large cities the water supply is a problem that is cared for by regularly constituted sanitary authorities. Pure water is a vital necessity, but the inhabitant of a city has no need to personally concern himself with the source of supply. In the country, however, the home builder must often decide the matter for himself, and it is the aim of this book to give him the needed directions for avoiding many errors and pitfalls that abound in this direction.
House construction, with its intricate problems, is also a more serious matter for the country dweller than for his city brother.
In the matter of food supply, the inhabitant of a country district is more fortunate. Fresh vegetables and dairy products are much more easily obtained, and their freshness and purity more dependable.
The article on water supply by Mr. Gerhard is authoritative, written, as it is, by a most eminent sanitarian. The publishers are to be congratulated upon the following valuable contribution to the same subject as regards the use of copper sulphate and the concise presentation of plans for mosquito extermination, while the extended work of Dr. Price and Dr. Baker's "Food Adulteration" are much to be commended. The two latter have been connected with the Department of Health of New York City, and have the advantage of experience in an organization which gives to the citizens of New York the protection to health that the wise use of science, knowledge, and money afford.
I trust that the notes I have added in the light of recent practice of the New York City Department of Health may make this material of the utmost practical value to the householder of to-day.
Through this Department of Health, New York City spent, during 1905, over $1,500,000, and for 1906 it has appropriated over $1,800,000. This vast sum of money is used for the sole purpose of safeguarding its citizens from disease. Sanitation in its varied branches is pursued as an almost exact science, and the efforts of trained minds are constantly employed in combating disease and promoting sanitation.
The cities care for their own, but the greater number of the inhabitants of this country must rely upon their individual efforts. Therefore, any dissemination of knowledge regarding sanitation is most worthy. This book has a useful mission. It is pregnant with helpful suggestions, and I most heartily commend its purpose and its contents.
THOMAS DARLINGTON, President of the Board of Health.
NEW YORK CITY.
Part I
WATER SUPPLY AND PURIFICATION
BY
WILLIAM PAUL GERHARD
CHAPTER I
Country Sources of Water Supply
The writer was recently engaged to plan and install a water-supply system for a country house which had been erected and completed without any provision whatever having been made for supplying the buildings and grounds with water. The house had all the usual appointments for comfort and ample modern conveniences, but these could be used only with water borrowed from a neighbor. In all parts of the country there are numerous farm buildings which are without a proper water-supply installation. These facts are mentioned to emphasize the importance of a good water supply for the country home, and to point out that water is unquestionably the most indispensable requirement for such structures.
Adequate Water Supply Important
But the advantages of a water supply are not limited to the dwelling house, for it is equally useful on the farm, for irrigation, and in the garden, on the golf grounds and tennis courts, in the barns and stables; it affords, besides, the best means for the much-desired fire protection. And, most important of all, an unstinted and adequate use of water promotes cleanliness and thereby furthers the cause of sanitation, in the country not less than in the city home.
The water supply for country houses has been so often discussed recently that the writer cannot hope to bring up any new points. This article should, therefore, be understood to offer simple suggestions as to how and where water can be obtained, what water is pure and fit for use, what water must be considered with suspicion, what water is dangerous to health, and how a source of supply, meeting the requirements of health, can be made available for convenient use.
Right here I wish to utter a warning against the frequent tendency of owners of country houses to play the role of amateur engineers. As a rule this leads to failure and disappointment. Much money uselessly spent can be saved if owners will, from the beginning, place the matter in experienced hands, or at least seek the advice of competent engineers, and adopt their suggestions and recommendations as a guide.
Points to be Borne in Mind
Many are the points to be borne in mind in the search for water. Science teaches us that all water comes from the clouds, the atmospheric precipitation being in the form of either rain, or dew, or snow. After reaching the earth's surface, the water takes three different courses, and these are mentioned here because they serve to explain the different sources of supply and their varied character.
A part of the water runs off on the surface, forming brooks, streams, and lakes, and if it falls on roofs of houses or on prepared catchment areas, it can be collected in cisterns or tanks as rain water. Another part of the water soaks away into pervious strata of the subsoil, and constitutes underground water, which becomes available for supply either in springs or in wells. A third part is either absorbed by plants or else evaporated.
In our search for a source of supply, we should always bear in mind the essential requirements of the problem. Briefly stated, these are: the wholesomeness of the water, the adequateness and steadiness of the supply, its availability under a sufficient pressure, insuring a good flow, and the legal restrictions with which many water-supply problems are surrounded.
The first essential requirement is that of wholesomeness. The quality of a water supply is dependent upon physical properties and upon chemical and bacteriological characteristics. Water, to be suitable for drinking, must be neither too hard nor too soft; it should not contain too many suspended impurities, nor too much foreign matter in solution. Pure water is colorless and without odor. But it must be understood that the quality cannot be decided merely by the color, appearance, taste, and odor. The chemical and bacteriological examinations, if taken together, form a much safer guide, and with these analyses should go hand in hand a detailed survey of the water source and its surroundings.
Relation of Water to Health
Any pronounced taste in the water renders it suspicious; an offensive smell points to organic contamination; turbidity indicates presence of suspended impurities, which may be either mineral or organic. But even bright and sparkling waters having a very good taste are sometimes found to be highly polluted. Hence, it should be remembered that neither bright appearance nor lack of bad taste warrants the belief that water is free from dangerous contamination.
It is a well-established fact now that there is a relation between the character of the water supply and the health of a community; and what is true of cities, villages, and towns, is, of course, equally true of the individual country house.
How Water Becomes Contaminated
There are numerous ways in which water may become polluted, either at the source or during storage or finally during distribution. Rain water, falling pure from the clouds, encounters dust, soot, decaying leaves and other vegetable matters, and ordure of birds on the roofs; its quality is also affected by the roofing material, or else it is contaminated in the cisterns by leakage from drains or cesspools. Upland waters contain generally vegetable matter, while surface water from cultivated lands becomes polluted by animal manure. River water becomes befouled by the discharge into it of the sewers from settlements and towns located on its banks. Subsoil water is liable to infiltration of solid and liquid wastes emanating from the human system, from leaky drains, sewers, or cesspools, stables, or farmyards; and even deep well water may become contaminated by reason of defects in the construction of the well.
During storage, water becomes contaminated in open reservoirs by atmospheric impurities; a growth of vegetable organisms or algae often causes trouble, bad taste, or odor; water in open house tanks and in cisterns is also liable to pollution. During distribution, water may become changed in quality, owing to the action of the water on the material of the pipes.
From what source shall good water be obtained? This is the problem which confronts many of those who decide to build in the country.
The usual sources, in their relative order of purity, are: deep springs and land or surface springs, located either above or below the house, but not too near to settlements; deep subterranean water, made available by boring or drilling a well; upland or mountain brooks from uninhabited regions; underground water in places not populated, reached by a dug or driven well; lake water; rain water; surface water from cultivated fields; pond and river water; and finally, least desirable of all, shallow well water in villages or towns. These various sources of supply will be considered farther on.
An Ample Volume Necessary
The second essential requirement is ample quantity. The supply must be one which furnishes an ample volume at all seasons and for all purposes.
What is a reasonable daily domestic consumption? The answer to this question necessarily depends upon the character of the building and the habits and occupation of its inmates. It is a universal experience that as soon as water is introduced it is used more lavishly, but also more recklessly and regardless of waste. For personal use, from twenty to twenty-five gallons per person should prove to be ample per day: this comprises water for drinking and cooking, for washing clothes, house and kitchen utensils, personal ablutions, and bathing; but, taking into account other requirements on the farm or of country houses, we require at least sixty gallons per capita per diem. To provide water for the horses, cows, sheep, for carriage washing, for the garden, for irrigation of the lawn, for fountains, etc., and keep a suitable reserve in case of fire, the supply should be not less than 150 gallons per person per day.
A Good Pressure Required
The third essential requirement is a good water pressure. Where a suitable source of water is found, it pays to make it conveniently available, so as to avoid carrying water by hand, which is troublesome and not conducive to cleanliness. A sufficient pressure is attained by either storing water at, or lifting it to, a suitable elevation above the point of consumption. In this respect many farm and country houses are found to be but very imperfectly supplied. Often the tank is placed only slightly higher than the second story of the house. As a result, the water flows sluggishly at the bathroom faucets, and, in case of fire, no effective fire stream can be thrown. Where a reservoir is suitably located above the house, the pressure is sometimes lost by laying pipes too small in diameter to furnish an ample stream. Elevated tanks should always be placed so high as to afford a good working pressure in the entire system of pipes. Where a tower of the required height is objectionable, either on account of the cost or on account of appearance, pressure tanks may be installed which have many advantages.
In selecting a source of water supply, the following points should be borne in mind for guidance: first, the wholesomeness of the water; next, the cost required to collect, store, and distribute the water; finally, where a gravity supply is unavailable, the probable operating expenses of the water system, cost of pumping, etc.
Collection of Rain Water
The collection of rain water near extensive manufacturing establishments is not advisable, except where arrangements are provided for either filtering or distilling the water. In the country, rain water is pure and good, if the precaution is observed to allow the first wash from roofs to run to waste. The rain may be either caught on the roofs, which must always have a clean surface and clean gutters, or else on artificially prepared catchment areas. As an example, I quote: "All about the Bermuda Islands one sees great white scars on the hill slopes. These are dished spaces, where the soil has been scraped off and the coral rock exposed and glazed with hard whitewash. Some of these are a quarter acre in size. They catch and carry the rainfall to reservoirs, for the wells are few and poor, and there are no natural springs and no brooks." (Mark Twain, "Some Rambling Notes of an Idle Excursion.")
After the close of the Boer War the English sent about 7,000 Boer prisoners of war to Bermuda, where they were encamped on some of the smaller islands of the group, and the entire water supply for the encampment was obtained by building artificial catchment areas as described in the above quotation.
Sometimes, instead of building underground cisterns, rain water is caught and stored in barrels above ground; if so, these should always be well covered, not only to avoid pollution, but to prevent the barrels from becoming mosquito breeders. Cisterns should always be built with care and made water-tight and impervious. The walls should be lined with cemented brickwork. In soil consisting of hard pan, cisterns in some parts of the country are built without brick walls, the walls of the excavation being simply cemented. I do not approve of such cheap construction, particularly where the cistern is located near a privy or cesspool. Pollution of cistern water is often due to the cracking of the cement lining. Overflows of cisterns should never be connected with a drain, sewer, or cesspool. Run the overflow into some surface ditch and provide the mouth with a fine wire screen, to exclude small animals. It is not recommended to build cisterns in cellars of houses.
Quality of Water Obtained from Lakes
Lakes yield, as a rule, a supply of clear, bright, and soft water. This is particularly the case with mountain lakes, because they are at a distance from sources of contamination. The character of the water depends upon whether the lake is fed by brooks, that is, by the rain falling upon the watershed, or also by springs. In one case the water is surface water exclusively; in the other, it is surface and underground water mixed. The purity also depends upon the depth of the lake and upon the character of its bottom.
Deep lakes furnish a better supply and clearer water than shallow ones. The solid matter brought into the lake by the brooks or rivers which feed it does not remain long in suspension, but soon settles at the bottom, and in this way some lakes acquire the wonderfully clear water and the beautiful bluish-green color for which they are far famed.
Strong Winds Dangerous on Lakes
Strong winds or currents at times stir up the mud from the bottom; hence, in locating the intake, the direction of the prevailing winds should be considered, if practicable. The suction pipe should always be placed in deep water, at a depth of at least fifteen to twenty feet, for here the water is purer and always cooler.
Settlements on the shores of a lake imply danger of sewage contamination, but the larger the lake, the less is the danger of a marked or serious pollution, if the houses are scattered and few.
Pools and stagnant ponds are not to be recommended as a source of supply. In artificially made lakes there is sometimes danger of vegetable pollution, and trouble with growth of algae. The bottom of such lakes should always be cleared from all dead vegetation.
Surface water may be obtained from brooks flowing through uninhabited upland or from mountain streams. Such water is very pure and limpid, particularly where the stream in its downward course tumbles over rocks or forms waterfalls. But, even then, the watershed of the stream should be guarded to prevent subsequent contamination. Larger creeks or rivers are not desirable as a source of supply, for settlements of human habitations, hamlets, villages, and even towns are apt to be located on the banks of the river, which is quite generally used—wrong as it is—as an outlet for the liquid wastes of the community, thus becoming in time grossly polluted. Down-stream neighbors are sure to suffer from a pollution of the stream, which the law should prevent.
The Water of Springs
The water of springs is subterranean, or ground water, which for geological reasons has found a natural outlet on the surface. We distinguish two kinds of springs, namely, land or surface springs, and deep springs. The former furnish water which originally fell as rain upon a permeable stratum of sand or gravel, underlaid by an impervious one of either clay or rock. Such water soaks away underground until it meets some obstacle causing it to crop out on the surface. Such spring water is not under pressure and therefore cannot again rise. Water from deep springs is rain water fallen on the surface of a porous stratum on a high level, and which passes under an impermeable stratum, and thus, being under pressure, rises again where an opening is encountered in the impervious stratum; these latter springs are really artesian in character.
Deep-spring water is less apt to be polluted than water from surface or land springs, for it has a chance in its flow through the veins of the earth to become filtered. Land springs always require careful watching, particularly in inhabited regions, to prevent surface contamination.
Not all Spring Water Pure
It is a popular fallacy that all spring water is absolutely pure and healthful. The above explanation will be helpful in pointing out how, in some cases, spring water may be nothing but contaminated ground water. Land springs in uncultivated and uninhabited regions, particularly in the mountains, yield a good and pure supply. But it is always advisable, when tapping a spring for water supply, to study its probable source, and carefully to inspect its immediate surroundings. The spring should be protected by constructing a small basin, or reservoir, and by building a house over this. The basin will also serve to store the night flow of the spring. Before deciding upon a supply from a spring, its yield should be ascertained by one of the well-known gauging methods. Springs are usually lowest in the months of October and November, though there is some difference in this respect between land springs and deep springs. The minimum yield of the spring determines whether it forms a supply to be relied upon at all times of the year.
If the spring is located higher than the grounds and buildings to be supplied, a simple gravity supply line may be carried from it, with pipes of good size, thus avoiding undue friction in the line, and stoppages. If lower than the house, the water from the spring must be raised by some pumping method.
All water found underground owes its origin to the rainfall. If concealed water is returned to the surface by natural processes it is called spring water, but if recovered by artificial means it is called well water.
Different Kinds of Wells
There are numerous kinds of wells, distinguished from one another by their mode of construction, by their depth from the surface, by the fact of their piercing an impervious stratum or merely tapping the first underground sheet of water, and by the height to which the water in them rises or flows. Thus we have shallow and deep wells, horizontal wells or infiltration galleries, open or dug wells, tube wells, non-flowing and flowing wells, bored, drilled, and driven wells, tile-lined and brick-lined wells, and combination dug-and-tubular wells.
When it is desired to provide a water supply by means of wells some knowledge of the geology of the region, of the character of the strata and of their direction and dip, will be very useful. In the case of deep wells, it is really essential. By making inquiries as to similar well operations in the neighborhood, one may gain some useful information, and thus, to some extent, avoid guesswork. When one must drill or bore through rock for a very deep well, which necessarily is expensive, much money, often uselessly spent, may be saved by consulting the reports of the State geologist, or the publications of the United States Geological Survey, or by engaging the services of an expert hydrogeologist.
"Water Finders"
It used to be a common practice to send for so-called "water finders," who being usually shrewd observers would locate by the aid of a hazel twig the exact spot where water could be found. In searching for water one sometimes runs across these men even to-day. The superstitious faith in the power of the forked twig or branch from the hazelnut bush to indicate by its twisting or turning the presence of underground water was at one time widespread, but only the very slightest foundation of fact exists for the belief in such supernatural powers.
In Europe, attention has again, during the past years, been called to this "method" of finding water, and it has even received the indorsement of a very high German authority in hydraulic engineering, a man well up in years, with a very wide practical experience, and the author of the most up-to-date hand-book on "Water Supply," but men of science have not failed to contradict his statements.
Definition of "Ground-water Level"
Water percolating through the soil passes downward by gravity until it reaches an impervious stratum. The surface of this underground sheet of water is technically called "water table" or ground-water level. The water is not at rest, but has a slow and well-defined motion, the rate of which depends upon the porosity of the soil and also upon the inclination or gradient of the water table. A shallow well may be either excavated or driven into this subsoil sheet of water. In populous districts, in villages, towns, but also near habitations, the soil from which water is obtained must, of necessity, be impregnated with organic waste matter. If, in such a surface well, the level of the water is lowered by pumping, the zone of pollution is extended laterally in all directions. Ordinary shallow well water should always be considered "suspicious water." There are two distinct ways in which surface wells are contaminated: one is by leakage from cesspools, sewers, privies, etc.; the other, just as important and no less dangerous, by direct contamination from the surface. The latter danger is particularly great in wells which are open at the surface, and from which water is drawn in buckets or pails. A pump well is always the safer of the two. Frogs, mice, and other small animals are apt to fall into the water; dust and dirt settle into it; the wooden curb and the rotten cover also contribute to the pollution; even the draw-buckets add to it by reason of being often handled with unclean hands.
Always avoid, in the country, drinking water from farmers' wells located near cesspools or privies. Such shallow wells are particularly dangerous after a long-protracted drought. It is impossible to define by measurement the distance from a cesspool or manure pit at which a well can be located with safety, for this depends entirely upon local circumstances. Contamination of shallow wells may, in exceptional cases, be avoided by a proper location of the well with reference to the existing sources of impurity. A well should always be placed above the source of pollution, using the word "above" with reference to the direction in which the ground water flows.
Precautions Regarding Wells
Other precautions to be observed with reference to surface wells are the following:
Never dig a well near places where soil contamination has taken or is taking place. Line the sides of the well with either brick, stone, or tile pipe, cemented in a water-tight manner to a depth of at least twenty feet from the surface, so that no water can enter except from the bottom, or at the sides near the bottom.
Raise the surface at the top of the well above the grade; arrange it so as to slope away on all sides from the well; cover it with a flagstone, and cement the same to prevent foreign matters from dropping into the well; make sure that no surface water can pass directly into the well; make some provision to carry away waste water and drippings from the well.
Shallow wells made by driving iron tubes with well points into the subsoil water are preferable to dug wells. Use a draw-pump in preference to draw buckets.
When a well is sunk through an impervious stratum to tap the larger supply of water in the deeper strata, we obtain a "deep well." Water so secured is usually of great purity, for the impurities have been filtered and strained out by the passage of the water through the soil. Moreover, the nature of the construction of deep wells is such that they are more efficiently protected against contamination, the sides being made impervious by an iron-pipe casing. In some rare cases, even deep wells show pollution due to careless jointing of the lining, or water follows the outside of the well casing until it reaches the deeper water sheet. Deep wells usually yield more water than shallow driven wells, and the supply increases perceptibly when the water level in the well is lowered by pumping. While surface wells draw upon the rainfall percolating in their immediate vicinity, deep wells are supplied by the rainfall from more remote districts. Deep wells are either non-flowing or flowing wells. When the hydrostatic pressure under which the water stands is sufficient to make it flow freely out on the surface or at the mouth of the well, we have a flowing, or true artesian well.
Character of Water From Deep Wells
Water from deep wells is of a cool and even temperature. It is usually very pure, but in some cases made hard by mineral salts in the water. Sulphur is also at times present, and some wells on the southern Atlantic coast yield water impregnated with sulphur gases, which, however, readily pass off, leaving the water in good condition for all uses. In many cases the water has a taste of iron. No general rule can be quoted as to the exact amount of water which any given well will yield, for this depends upon a number of factors. Increasing the diameter of very deep wells does not seem to have any marked effect in increasing the supply. Thus, a two-foot well gives only from fifteen to thirty per cent more water than a three-inch-pipe well. This rule does not seem to apply to shallow wells of large diameter, for here we find that the yield is about in proportion to the diameter of the well.
It is interesting to note the fact that wells located near the seashore, within the influence of the tide, vary in the hourly flow. According to Dr. Honda, of the University of Tokio, there is "a remarkable concordance between the daily variations in the level of the tides and the water level in wells." The water in wells one mile from the seashore was found to stand highest at high tide. The daily variation amounted to sixteen centimeters, or a little over six inches. A similar variation was observed by the writer in some flowing wells located on the north shore of Long Island. Dr. Honda found also that the water level in wells varied with the state of the barometer, the water level being lowered with a rise in the barometer.
Where a large supply is wanted a series of wells may be driven, and, as the expense involved is considerable, it is always advisable to begin by sinking a smaller test well to find out whether water may be had.
Ground water may also be recovered from water-bearing strata by arranging horizontal collecting galleries with loose-jointed sides through which the water percolates. Such infiltration galleries have been used in some instances for the supply of towns and of manufacturing establishments, but they are not common for the supply of country houses.
Laws Regulating Appropriation of Water
Persons contemplating the establishment of a system of water supply in the country should bear in mind that the taking of water for supply purposes is, in nearly all States, hemmed in by legal restrictions. The law makes a distinction between subterranean waters, surface waters flowing in a well-defined channel and within definite banks, and surface waters merely spread over the ground or accumulated in natural depressions, pools, or in swamps. There are separate and distinct laws governing each kind of water. It is advisable, where a water-supply problem presents itself, to look up these laws, or to consult a lawyer well versed in the law of water courses.
If it is the intention to take water from a lake, the property owner should make sure that he owns the right to take such water, and that the deed of his property does not read "to high-water mark only." The owner of a property not abutting on a lake has no legal right to abstract some of the water from the lake by building an infiltration gallery, or a vertical well of large diameter intended for the same purpose. On the other hand, an owner may take subterranean water by driving or digging a well on his own property, and it does not matter, from the law's point of view, whether by so doing he intercepts partly or wholly the flow of water in a neighboring well. But, if it can be shown that the subterranean water flows in a well-defined channel, he is not permitted to do this. The water from a stream cannot be appropriated or diverted for supply or irrigation purposes by a single property holder without the consent of the other riparian owners, and without compensation to them.
CHAPTER II
Appliances for Distributing Water
We have so far discussed only the various sources of potable water. We must now turn our attention to the mechanical means for making it available for use, which comprise appliances for lifting, storing, conveying, distributing, and purifying the water.
The location of the source of supply with reference to the buildings and grounds decides generally the question whether a gravity supply is feasible or whether water must be pumped. The former is desirable because its operating expenses are almost nothing, but it is not always cheapest in first cost. Rather than have a very long line of conduit, it may be cheaper to pump water, particularly if wind or water power, costing nothing, can be used.
Machines for Pumping
When it becomes necessary to pump water, there are numerous machines from which to choose; only the more important ones will be considered. We may use pumps operated by manual labor, those run by animal power, pumping machinery using the power of the wind or that of falling or running water; then there are hot-air, steam, and electric pumps, besides several forms of internal-combustion engines, such as gas, gasoline, and oil engines. Each has advantages in certain locations and under certain conditions.
Of appliances utilizing the forces of Nature, perhaps the simplest efficient machine is the hydraulic ram. While other machines for lifting water are composed of two parts, namely, a motor and a pump, the ram combines both in one apparatus. It is a self-acting pump of the impulse type, in which force is suddenly applied and discontinued, these periodical applications resulting in the lifting of water. Single-acting rams pump the water which operates them; double-acting rams utilize an impure supply to lift a pure supply from a different source.
The advantages of the ram are: it works continuously, day and night, summer and winter, with but very little attendance; no lubrication is required, repairs are few, the first cost of installation is small. Frost protection, however, is essential. The disadvantages are that a ram can be used only where a large volume of water is available. The correct setting up is important, also the proper proportioning in size and length of drive and discharge pipes. The continual jarring tends to strain the pipes, joints, and valves; hence, heavy piping and fittings are necessary. A ram of the improved type raises water from twenty-five to thirty feet for every foot of fall in the drive pipe, and its efficiency is from seventy to eighty per cent.
Running water is a most convenient and cheap power, which is often utilized in water wheels and turbines. These supply power to run a pump; the water to be raised may come from any source, and the pump may be placed at some distance from the water wheel. Where sufficient fall is available—at least three feet—the overshot wheel is used. In California and some other Western States an impulse water wheel is much used, which is especially adapted to high heads.
Windmills Used for Driving Pumps
The power of the wind applied to a windmill is much used for driving pumps. It is a long step forward from the ancient and picturesque Dutch form of windmill, consisting of only four arms with cloth sails, to the modern improved forms of wheels constructed in wood and in iron, with a large number of impulse blades, and provided with devices regulating the speed, turning the wheel out of the wind during a gale, and stopping it automatically when the storage tank is filled. The useful power developed by windmills when pumping water in a moderate wind, say of sixteen miles an hour velocity, is not very high, ranging from one twenty-fifth horse-power for an eight and one-half foot wheel to one and one-half horse-power for a twenty-five foot wheel. The claims of some makers of windmills as to the power developed should be accepted with caution.
The chief advantage is that, like a ram, the windmill may work night and day, with but slight attention to lubrication, so long as the wind blows. But there are also drawbacks; it requires very large storage tanks to provide for periods of calm; the wheel must be placed sufficiently exposed to receive the full wind force, either on a tower or on a high hill, and usually this is not the best place to find water. Besides, a windmill tower, at least the modern one, is not an ornamental feature in the landscape. It is expensive when built sufficiently strong to withstand severe winter gales. During the hot months of the year, when the farmer, the gardener, and the coachman require most water, the wind is apt to fail entirely for days in succession.
The Use of Engines
If water is not available, and wind is considered too unreliable, pumping must be accomplished by using an engine which, no matter of what form or type, derives its energy from the combustion of fuel, be the same coal, wood, charcoal, petroleum or kerosene, gas, gasoline, or naphtha. The use of such pumping engines implies a constant expense for fuel, operation, maintenance, and repairs. In some modern forms of engines this expense is small, notably so in the oil engine, and also in the gasoline engine; hence these types have become favorites.
Advantages of Pumping Engines
An advantage common to all pumping engines is that they can be run at any time, not like the windmill, which does not operate in a light breeze, nor like the ram, which fails when the brook runs low. Domestic pumping engines are built as simple as possible, so that the gardener, a farm hand, or the domestic help may run them. Skill is not required to operate them, and they are constructed so as to be safe, provided ordinary intelligence is applied.
In using a fuel engine it is desirable, because of the attendance required, to take a machine of such capacity and size that the water supply required for two or three days may be pumped to the storage tank in a few hours.
Expansive Force of Heated Air Utilized
A favorite and extensively used type of domestic pump is the hot-air engine, in which the expansive force of heated air is used to do useful work. Among the types are simple and safe machines which do not easily get out of order. They are started by hand by giving the fly wheel one or more revolutions. If properly taken care of they are durable and do not require expensive repairs.
Gas and Gasoline Engines
In gas engines power is derived from the explosion of a mixture of gas and air. Where a gas supply is available, such engines are very convenient, for, once started, they will run for hours without attention. They are economical in the consumption of gas, and give trouble only where the quality of gas varies.
Owing to the unavailability of gas on the farm and in country houses, two other forms of pumping engines have been devised which are becoming exceedingly popular. One is the gasoline, the other is the oil engine. Both resemble the gas engine, but differ from it in using a liquid fuel which is volatilized by a sprayer. Gasoline engines are now brought to a high state of perfection.
Kerosene or Crude Oil as Fuel
In recent years, internal-combustion engines which use heavy kerosene or crude oil as fuel have been introduced. These have two palpable advantages: first, they are safer than gasoline engines; second, they cost less to run, for crude oil and even refined kerosene are much cheaper than gasoline. Oil engines resemble the gas and gasoline engines, but they have larger cylinders, because the mean effective pressure evolved from the explosion is much less than that of the gasoline engines.
Oil engines for pumping water are particularly suitable in regions where coal and wood cannot be obtained except at exorbitant cost. Usually, the engine is so built as to be adapted for other farm work. It shares this advantage with the gasoline engine. Oil engines are simple, reliable, almost automatic, compact, and reasonable in first cost and in cost of repairs. There are many forms of such engines in the market. To be successful from a commercial point of view, an oil engine should be so designed and built that any unskilled attendant can run, adjust, and clean it. The cost of operating them, at eight cents per gallon for kerosene, is only one cent per hour per horse-power; or one-half of this when ordinary crude oil is used. The only attention required when running is periodical lubrication and occasional replenishing of the oil reservoir. The noise of the exhaust, common to all engines using an explosive force, can be largely done away with by using a muffler or a silencer. The smell of oil from the exhaust likewise forms an objection, but can be overcome by the use of an exhaust washer.
Steam and Electric Pumps
The well-known forms of steam-pumping engines need not be considered in detail, because high-pressure steam is not often available in country houses. Where electric current is brought to the building, or generated for lighting purposes, water may be pumped by an electric pump. Electric motors are easy and convenient to run, very clean, but so far not very economical. Electric pumps may be arranged so as to start and stop entirely automatically. Water may be pumped, where electricity forms the power, either by triplex plunger pumps or by rotary, screw, or centrifugal pumps.
Pumps Worked by Hand
Space forbids giving a description of the many simpler devices used for lifting water. In small farmhouses lift and force pumps worked by hand are now introduced, and the old-fashioned, moss-covered draw-bucket, which is neither convenient nor sanitary, is becoming a relic of past times.
Reservoirs and Storage Tanks
The water pumped is stored either in small masonry or earth reservoirs, or else in storage tanks of either wood, iron, or steel, placed on a wood or steel tower. Wooden tanks are cheap but unsightly, require frequent renewal of the paint, and give trouble by leaking, freezing, and corrosion of hoops. In recent years elevated tanks are supplanted by pressure tanks. Several such systems, differing but little from one another, are becoming quite well known. In these water is stored under suitable pressure in air-tight tanks, filled partly with water and partly with air.
A Simple Pressure System
One system consists of a circular, wrought-steel, closed tank, made air- and water-tight, a force pump for pumping water into the tank, and pipe connections. The tank is placed either horizontally or vertically in the basement or cellar, or else placed outdoors in the ground at a depth below freezing. Water is pumped into the bottom of the tank, whereby its air acquires sufficient pressure to force water to the upper floors.
This simple system has some marked advantages over the outside or the attic tank. In these, water gets warm in summer and freezes in winter. Vermin and dust get into the tank, and the water stagnates. In the pressure tank, water is kept aerated, cool, and clean.
Another pressure tank has an automatic valve, controlled by a float and connected with suction of pump. It prevents the tank from becoming water-logged by maintaining the correct amount of air inside.
An Ideal System for a Country House
Still another system using pressure tanks is more complete than either of the others, comprising engine, pump, air compressor, a water tank, and also an air tank. It is best described by a recent example constructed from plans and under the direction of the writer. The buildings supplied with water comprise the mansion, the stable, the cottage, and a dairy, and the pumping station is placed near the shore of the lake from which the supply is taken. See Figs. 1 and 2.
The pump house is about 20 feet by 27 feet, and contains a water-storage tank 6 feet in diameter and 13-1/2 feet long, of a capacity of 3,000 gallons; an air tank of same dimensions as the water tank, holding air under 150 pounds pressure; a 10 horse-power gasoline engine, direct-connected, by means of friction clutch, with an air compressor and also with a triplex pump of 75 gallons capacity per minute.
The water in the tank is kept under 75 pounds pressure, and at the hydrant near the house, located about 100 feet above the pumping station, there is an available pressure of 33 pounds. The last drop of water flows from the water tank under the full pressure of 75 pounds at the pumping station. The suction pipe into the lake is 4 inches and is provided with well strainers to prevent clogging.
The cost of pumping water by this system is quite reasonable. The gasoline engine requires per horse-power per hour about 1-1/4 gallons of gasoline, and at sixteen cents per gallon this makes the cost for 1,000 gallons pumped about five cents. To this expense should, however, be added the cost of lubricating oil, repairs, amount for depreciation, and the small cost for labor in running the engine.
Water pipes forming a distribution system should always be chosen generous in diameter, in order to avoid undue loss of pressure by friction. Where fire hydrants are provided, the size of the water main should not be below four inches. All branches should be controlled by shut-offs, for which the full-way gate valves are used in preference to globe valves. Pipe-line material is usually galvanized, screw-jointed wrought iron for sizes up to four inches.
In conclusion, a word about water purification. Where the quality of the water supply is not above suspicion it may be improved by filtration. A filter should never be installed without the advice of a qualified expert, for there are numerous worthless devices and few really efficient ones. Where a filter is not available, the water used for drinking should be boiled or sterilized if there is the slightest doubt as to its wholesomeness.
CHAPTER III
Purifying Water by Copper Sulphate
From the standpoint of the health of the community, the most vital problem is to get pure water. Almost equally important, when comfort and peace of mind is considered, is the procuring of sweet water. The wise owner of a country home looks to the water supply upon which his family is dependent. The careful farmer is particular about the water his stock, as well as his family, must drink. But careless persons constitute the large majority. Most people in the city and in the country pay no attention to their drinking water so long as it "tastes all right."
Clear Water Often Dangerous
Some years ago the inhabitants of Ithaca, N. Y., furnished a pitiful example of this foolhardy spirit. For a year previous to the breaking out of the typhoid epidemic, the public was warned, through the local and the metropolitan press, of the dangerous condition of Ithaca's water supply. Professors of Cornell College joined in these warnings. But the people gave no heed, probably because the water was clear and its taste sweet and agreeable. As was the case in this instance, bacteria are tolerated indefinitely, and it is only an alarming increase in the death rate that makes people careful. Then they begin to boil the water—when it is too late for some of them.
Bad-Tasting Water not Always Poisonous
But let the taste become bad and the odor repulsive, and a scare is easily started. "There must be dead things in the water, or it wouldn't taste so horrible," is the common verdict. Some newspaper seizes upon the trouble and makes of it a sensation. The ubiquitous reporter writes of one of "the animals" that it "looks like a wagon wheel and tastes like a fish." With such a remarkable organism contaminating one's drink no wonder there is fear of some dread disease. The water is believed to be full of "germs"; whereas the pollution is entirely due to the presence of algae—never poisonous to mankind, in some cases acting as purifying agents, but at certain seasons of the year imparting a taste and odor to the water that cannot be tolerated.
Algae—what are they? They are aquatic plants. Algae are not to be confounded with the water vegetation common to the eye and passing by the term weeds. Such plants include eelgrass, pickerel weed, water plantain, and "duckmeat"—all of which have roots and produce flowers. This vegetation does not lend a bad odor or taste to the water. In itself it is harmless, although it sometimes affords a refuge for organisms of a virulent type.
But when the aquatic vegetation of the flowering variety is eliminated from consideration, there still remains a group of water plants called algae. They comprise one-fifth of the known flowerless plants. They are the ancestors of the entire vegetable kingdom. Those whose habitat is the sea number the largest plants known in nature. Certain forms found in the Pacific are supposed to be 800 feet in length; others are reported to be 1,500 feet long. The marine variety are familiar as the brown kelps and the wracks, which are very common along our Northern coast.
Plants Which Pollute Drinking Water
The fresh-water algae are usually grass green in color. This green variety is often seen as a spongy coating to the surface of stagnant pools, which goes by the name of "frog spawn" or "pond scum." One of this description, Spirogyra, has done thousands of dollars' worth of damage by smothering the life out of young water-cress plants in artificial beds constructed for winter propagation. When the cress is cut the plants are necessarily left in a weakened condition, and the algae form a thick mat over the surface of the water, thus preventing the growth of the cress plants and oftentimes killing them. The absolute necessity of exterminating these algae led to the perfection of the copper-purification process.
It is, however, a variety of algae not easily detected that contaminates the water. So long as they are in a live, healthy condition they benefit drinking water by purifying it. Indeed, some scientists have attributed the so-called self-purification of a stream entirely to the activities of these plants. Of such, one form, Chlamydomonas, is bright grass green in appearance. But the largest group—the plants which have the worst reputation as polluters of drinking water—are popularly known as the "blue-green algae" (Schizophyceae). The common name tells the color of these plants, although there are exceptions in this respect, some of them showing shades of yellow, brown, olive, chocolate, and purplish red. This variety of algae flourishes in the summer months, since a relatively high temperature and shallow stagnant water favor its germination. If the pond begins to dry up, the death of the organisms takes place, and the result is a most disagreeable, persistent odor which renders the water unfit for drinking purposes. This result is chemically due to the breaking down of highly organized compounds of sulphur and phosphorus in the presence of the large amount of nitrogen contained in these plants. Decomposition is not necessary for some of the blue greens to give off a bad odor, however. A number of them, on account of their oil-content, produce an odor when in a healthy condition that is sometimes likened to raw green corn or to nasturtiums, but usually it cannot be so pleasantly described.
The Department of Agriculture has been able to solve the problem of exterminating algae from water supplies.[1] The department has done more; for it has succeeded in perfecting a method by which a reservoir contaminated with typhoid or other pathogenic bacteria can be purified. The work was begun with an inquiry into the extent of the trouble from algal pollution. Letters were addressed to some five hundred engineers and superintendents of water companies scattered all over the United States. The replies, which came from almost every State in the Union, were burdened with one complaint—"Algae are our worst pest"; and with one prayer—"Come over into Macedonia, and help us."
A Cheap and Available Remedy for Algae
Convinced of the need of earnest work, extensive laboratory experiments were inaugurated. The problem presented was this: the remedy must not only be readily available, but it must be cheap, that advantage may be taken of it by the poorest communities, as well as by those owning large reservoirs. Above all, the remedy must be absolutely harmless to man; the poison used to exterminate algae must not in any way affect the water drinkers. A large number of substances were used in the experiments before the final decision rested with copper sulphate. This salt is very poisonous to algae. On the other hand, copper in solution just strong enough to destroy algal growth could not possibly injure man; in fact, the temporary presence of such a small amount of copper in drinking water could not be detected.
A Practical Demonstration
The results in the laboratory being successful, the next step was to make a practical demonstration of the value of the method. This was first done in the fall of 1901. At Ben, Va., water cress is grown in large quantities during the winter, when it is a valuable market crop. Dams are constructed across a stream in such a manner as to enable the maintenance of a water level not too high for the growth of plants; when a freeze is threatened the plants can be flooded. In the cress beds selected for the experiments the water is obtained from a thermal spring whose temperature throughout the year is about 70 deg. F. This temperature is particularly favorable to the growth of "frog spawn." After the cress was cut for market, the algae frequently developed so rapidly as to smother the life out of the weakened plants. When this occurred, the practice was to rake out both water cress and algae and reset the entire bed. This was not only expensive; half the time it failed to exterminate the pest. It was, therefore, most desirable to devise a method of ridding the bed of algal growth without injuring the cress.
The Copper-sulphate Method Tested
Here the copper-sulphate method was put to a practical test. At the outset a strong solution was sprayed on the algae which coated the surface of the pond. This only killed the algal growth with which the particles of copper came in contact and left the main body of algae unaffected. Then trial was made of dissolving the copper directly in the water, and the result was most satisfactory. The solution used was that of 1 part of copper to 50,000,000 parts of water.
Growers need have no trouble in the future. They need have no fear of employing the method, as the copper solution required for killing the algae could not possibly injure water cress, provided ordinary care is used in the work. As to the frequency of treatment required, one or two applications a year will generally be found sufficient, as this letter, received from the manager of the Virginia company, goes to show:
"The 'moss' has given me no trouble at all this winter; in fact, I have for six months had to resort to the copper sulphate only once.... All the conditions were favorable last fall and early winter for a riot of 'moss,' but it did not appear at all until just a few days ago, and then yielded to treatment much more readily than it did when I first began to use the copper." This letter was written over three years after Dr. Moore made his experiment in these cress beds.
Satisfied with the results attained in exterminating algal growth in water-cress beds, attention was next given to reservoirs. Some fifty water supplies were treated during the summer of 1904, and in every case success attended the copper cure. In one respect the results were surprising. It was found that in practice the copper-sulphate method worked better than in theoretic experimentation; results in large reservoirs were more pronounced than in the laboratory. In fact, it developed that the solution necessary to kill algae in the laboratory must contain from five to twenty times as much copper as that contained in a solution which will exterminate algal growth in its natural habitat. This is not easily explained, if it can be explained at all. The test reason advanced is that only the most resistant organisms stand transplanting to an artificial environment. But, after all, the important point is that the new method works better in practice than was expected.
A Prescription for the Copper Cure
Thus the department is able to announce that the process is no longer in the experimental stage, and also to say what conditions must be known in determining the proper quantity of copper sulphate for destroying algae, together with a prescription for the copper cure. Here it is, for the benefit of careful persons who will use the method with proper intelligence: "The importance of knowing the temperature of the contaminated water is second only to the necessity of knowing the organism present. With increase of temperature the toxicity of a given dilution increases, and vice versa. Assuming that 59 deg. F. is the average temperature of reservoirs during the seasons when treatment is demanded, the quantity of copper should be increased or decreased approximately 2.5 per cent for each degree below or above 59 deg. F.
"Similar scales should be arranged for the organic content and the temporary hardness of the water. With the limited data at hand it is impracticable to determine these figures, but an increase of 2 per cent in the quantity of copper for each part per 100,000 of organic matter and an increase of 0.5 to 5 per cent in the proportion of copper for each part per 100,000 of temporary hardness will possibly be found correct. The proper variation in the increase due to hardness will depend upon the amount of dissolved carbon dioxide; if very small, 5 per cent increase is desirable; if large, 0.5 per cent is sufficient."
The information in this prescription is to be used in connection with a table[2] published by the Department of Agriculture. This table gives the number of parts of water to one part of copper sulphate necessary to kill the various forms of algae which are listed. The formulae vary from 1 part of copper to 100,000 parts of water, necessary to destroy the most resistant and very rare forms (three of these are listed), to 1 part of copper in 25,000,000 parts of water, which is a sufficiently strong solution to exterminate Spirogyra, the cress-bed pest. By far the majority of forms do not require a solution stronger than that of 1 part of copper to 1,000,000 parts of water.
What the Agricultural Department is Doing
It is true that the department is not now holding out, directly, a helping hand to the owner of a country place, or to the farmer, in this campaign of purifying drinking water. In the first place, the greatest good of the greatest number demands that large reservoirs, which supply a great number of people with drinking water, ought to be considered first. Such supplies, moreover, are most frequently contaminated. Where fifty reservoirs were treated last summer, ten times that number will be "cured" this summer. It will be readily seen, therefore, that in conducting such a large number of experiments—considering preliminary reports, prescribing for treatment, and keeping proper account of results—the department, with a limited force and limited facilities, has its hands more than full.
More important still, there is an absolute need of the services of some expert on the ground. While an algologist is a functionary not generally employed by water companies—in fact, a man trained in the physiology of algae is difficult to find—nevertheless, it is highly important, as the department views it, to have the cooeperation of an expert versed to some extent in the biological examination of drinking water. In other words, the copper cure is not a "patent medicine," with printed directions which any person could follow. Intelligence and care are absolutely essential in the use of this treatment. Furthermore, each case must be treated as a distinct and separate case, as a physician would treat a patient.
Actual Purification Simple
Suppose, however, an owner of a country place, which is dependent upon a fresh-water pond for its water supply, finds that his drinking water is contaminated, that the taste and odor are such as to render the water unfit for use. There is no reason why he should not treat the supply, provided he is properly careful. When the nature of the polluting organism is definitely determined and the average temperature of the water observed, then the necessary formula can be decided upon. First, of course, the pond must be plotted, the depth found, and the capacity computed. The department will willingly furnish data for this purpose, together with blanks upon which to submit details as to contaminating organisms and water temperature, to any applicant. Once the proper solution is determined upon, the actual work of purification is most simple. In the following directions the department outlines the most practicable method of introducing the copper sulphate into a water supply:
Directions for the Copper Cure
"Place the required number of pounds of copper sulphate in a coarse bag—gunny sack or some equally loose mesh—and, attaching this to the stern of a row-boat near the surface of the water, row slowly back and forth over the reservoir, on each trip keeping the boat within ten to twenty feet of the previous path. In this manner about a hundred pounds of copper sulphate can be distributed in one hour. By increasing the number of boats, and, in the case of deep reservoirs, hanging two or three bags to each boat, the treatment of even a large reservoir may be accomplished in from four to six hours. It is necessary, of course, to reduce as much as possible the time required for applying the copper, so that for immense supplies, with a capacity of several billion gallons, it would probably be desirable to use a launch, carrying long projecting spars to which could be attached bags containing several hundred pounds of copper sulphate.
"The substitution of wire netting for the gunny-sack bag allows a more rapid solution of the sulphate, and the time required for the introduction of the salt may thus be considerably reduced. It is best to select as warm a day for treatment as circumstances will permit."
Cost of the Treatment
Not difficult, one would say. No—when the proper solution is determined; to reach that determination is the difficulty. That the method can be tried "at home" is proved by the results obtained by the owner of a country home in the vicinity of New York. Tired of consulting engineers, who looked at his water supply, informed him that they could do nothing, and then charged him a big fee (to one he paid $250), this owner resorted to the copper-sulphate treatment. The cure cost the man just $2—but let his letter to the department tell the story:
"My place in the country is located at Water Mill, in the township of Southampton, in Long Island. I purchased it in April, 1902, and was largely influenced in selecting this piece of land by the beauty of a pond which bounds it on the east. This little body of water covers about two acres, is fed by numerous springs, and discharges into Mecox Bay, the southern boundary of the land. When I bought the place the pond was filled with clear water. About the middle of the following June algae began to show, and in August the surface was almost entirely covered by the growth. The odor was offensive, and myriads of small insects hovered over the masses of algae much of the time. I consulted two engineers interested in the storage of water, and they told me that nothing could be done. The condition was so objectionable that I planned to plant a thick hedge of willows along the bank to shut off the view of the pond from the house.... I examined the pond on June 15th and found large masses of algae covering an area several hundred feet in length and from twenty to forty feet in width. No microscopical examination was made of the growth, but I was informed that it seemed to be largely composed of filaments of Spirogyra and other Confervae. On June 18th the treatment was begun.... In one week the growth had sunk and the pond was clear water. I examined the pond September 15th and found it still clear.
"The use of the sulphate of copper converted an offensive insect-breeding pond into a body of beautifully clear water. The pond was full of fish, but the copper did not seem to harm them."
Effect of Copper Sulphate on Fish
Native trout were not injured when the large reservoir at Cambridge, N. Y., was purified by the copper treatment. A slightly different result, in this respect, was reported from Elmira, N. Y., however. Part of the report is as follows:
"The effect of the copper-sulphate treatment on the different animal life was as follows: numerous 'pollywogs' killed, but no frogs; numerous small (less than two inches long) black bass and two large ones (eight inches long) killed; about ten large 'bullheads' were killed, but no small ones; numerous small (less than two inches long) 'sunfish' were killed, but no large ones.
"The wind brought the dead fish to the corners of the reservoir, and it was very little trouble to remove them. No dead fish were seen twenty-four hours after completion of the treatment."
The injury done by copper sulphate to fish is a more serious matter than was at first supposed. Brook trout are, apparently, the least resistant to the salt. A Massachusetts trout pond stocked with eight-inch trout lost forty per cent as a result of the introduction of a strong solution of copper sulphate. The Bureau of Fisheries is working in conjunction with the Division of Plant Physiology in this matter, and it is hoped to secure reliable information. In the meantime, owners of ponds stocked with game fish would do well to take great care before resorting to the copper cure for algae—that is, if they hesitate to lose a part of the fish.
Water May be Drunk During Treatment
When a pond or reservoir is treated with the proper amount of copper sulphate to remove algae—except in the case of the few very resistant forms requiring a stronger solution than 1 part of copper to 1,000,000 parts of water—there is no need of discontinuing the use of the water supply during treatment; the water may be drunk with impunity. But when water known to be polluted with pathogenic bacteria is sterilized by means of copper sulphate in strong solution, it is just as well to discontinue the use of the water for drinking purposes for not more than twenty-four hours. Even then, this is an overcareful precaution rather than a necessity.
Experiments conducted with great care and thoroughness demonstrate that at room temperature, which is near the temperature of a reservoir in summer, a solution of 1 part of copper to 100,000 parts of water will destroy typhoid bacteria in from three to five hours. Similar experiments have proved that a copper solution of like strength is fatal to cholera germs in three hours, provided the temperature is above 20 deg. F. As was the case with algae, bacteria were found to be much more sensitive to copper when polluting water than when grown in artificial media.
The Use of Copper Tanks
The toxic effect of metallic copper upon typhoid bacteria in water gives some hints as to prevention of the disease by the use of copper tanks. This should not altogether take the place of the boiling of the water; it is useful in keeping it free from contamination, although water allowed to stand in copper receptacles for a period of from twenty-four to forty-eight hours at room temperature would be effectively sterilized, no matter what its contamination and no matter how much matter it held in suspension. But in order to insure such results the copper must be kept thoroughly clean. This polishing is not, as was popularly supposed, to protect the consumer from "copper poisoning," but to prevent the metal from becoming so coated with foreign substances that there is no contact of the copper with the water, hence no antiseptic quality.
Dr. Henry Kreamer, of Philadelphia, proved that within four hours typhoid germs were completely destroyed by the introduction into the polluted water of copper foil.
"Granting the efficiency of the boiling of water for domestic purposes, I believe that the copper-treated water is more natural and more healthful.... The intestinal bacteria, like colon and typhoid, are completely destroyed by placing clean copper foil in the water containing them.
"Pending the introduction of the copper treatment of water on a large scale, the householder may avail himself of a method for the purification of drinking water by the use of strips of copper foil about three and one-half inches square to each quart of water, this being allowed to stand overnight, or from six to eight hours at the ordinary temperature, and then the water drawn off or the copper foil removed."
Although a splendid antiseptic, copper in weak solution is not harmful, no more so than the old copper utensils used by our forefathers were harmful. Undoubtedly they were of benefit, and the use of them prevented the growth of typhoid and other bacteria. People of to-day might well go back to copper receptacles for drinking water.
FOOTNOTES:
[1] For published reports of the work, see Bulletins 64 and 76, Bureau of Plant Industry, U. S. Department of Agriculture; reports prepared by Dr. George T. Moore and his assistant, Mr. Karl F. Kellerman.
[2] See Bulletin No. 76, supra.
CHAPTER IV
Ridding Stagnant Water of Mosquitoes
Because of the serious and often fatal injury it inflicts on man, the most dangerous animal known is the mosquito. Compared with the evil done by the insect pest, the cobra's death toll is small. This venomous serpent is found only in hot countries, particularly in India, while mosquitoes know no favorite land or clime—unless it be Jersey. Arctic explorers complain of them. In Alaska, it is recorded by a scientist that "mosquitoes existed in countless millions, driving us to the verge of suicide or insanity." A traveler on the north shore of Lake Superior, when the snow was several feet deep, and the ice on the lake five feet in thickness, relates that "mosquitoes appeared in swarms, literally blackening the banks of snow in sheltered places."
Mosquitoes Responsible for Yellow Fever
In the temperate zone this evil-breeding insect was, until recent years, considered more in the light of an exasperating pest. It is now known, however, that malaria is due entirely to the bites of mosquitoes. But it is in the tropical countries that their deadliest work is done. There, it has been proved beyond question, the mosquitoes are responsible for the carriage of yellow fever. If, in a yellow-fever ridden region, one were to live entirely in an inclosure, carefully protected with proper screens—as certain entomologists did—there practically would be no danger from the dread disease, even if all other precautions were neglected.
Effect of a Mosquito Bite
The crime committed by the mosquito against its innocent victim, man, is more in the nature of manslaughter than of murder, according to the authorities. There is no premeditated malice. "A mosquito bites primarily to obtain food," says a leading entomologist; "there is neither malice nor venom in the intent, whatever there may be in the act." There isn't great comfort in the intelligence conveyed by the scientist, nor in his further observation:
"Theoretically, there would seem to be no reason why there should be any pain from the introduction of the minute lancets of the insects, and the small amount of bloodletting is usually a benefit rather than otherwise. Unfortunately, however, in its normal condition the human blood is too much inclined to clot to be taken unchanged into the mosquito stomach; hence, when the insect bites, a minute droplet of poison is introduced, whose function it is to thin out the fluid and make it more suitable for mosquito digestion. It is this poison that sets up the inflammation and produces the irritation or swelling.... The pain is caused entirely by the action of the poison in breaking up the blood, and, as the first act of a biting mosquito is to introduce the poison into the wound, the pain and inflammation will be the same, whether the insect gets its meal or not. In fact, it has been said that if a mosquito be allowed to suck its fill and then fly, the bite will not itch, and there is just a basis of justification for this."
To make a scientific inquiry into the habits of the mosquito, and to do it patiently, one should be far from the maddening swarms, or at least effectively screened in. Then it would be possible to believe the statement of the Government's entomologist that not "one mosquito in a million" ever gets the opportunity to taste the blood of a warm-blooded animal. As proof of this there are, in this country, great tracts of marshy land never frequented by warm-blooded animals, and in which mosquitoes are breeding in countless numbers. The point is emphasized by the prevalence of mosquitoes in the arctic circle and other uninhabited regions.
If this gory insect does not live by blood alone, how is it nourished? Female mosquitoes are by nature vegetarians; they are plant feeders. Why they should draw blood at all is a question which remains unsolved by entomologists—as well as by the suffering victims. The females have been observed sucking the nectar from flowers; obtaining nutriment from boiled potatoes, even from watermelon rinds, from which they extract the juice. As regards the blood habit, the male mosquito is a "teetotaler." Just how this male insect lives, scientists have not determined. He may not take nourishment at all. At any rate, the mouth parts of the male are so different from those of the female that it is probable his food is obtained differently. The male is often seen sipping at drops of water, and a taste for molasses is ascribed to the male mosquito by one authority.
Presence of Mosquitoes Depends Upon Winds
A common remark heard along the Jersey shore, also on Long Island, is this: "When we have a sea breeze we are not troubled with mosquitoes, but when there comes a land breeze they are a pest." While this observation is true, the reasons therefore entertained by the unscientific mind are erroneous. The matter of the absence or abundance of mosquitoes in varying winds is closely related to the inquiry which entomologists have made: how far will mosquitoes fly? Says one investigator:
"The migration of mosquitoes has been the source of much misapprehension on the part of the public. The idea prevalent at our seaside resorts that a land breeze brings swarms of mosquitoes from far inland is based on the supposition that these insects are capable of long-sustained flight, and a certain amount of battling against the wind. This is an error. Mosquitoes are frail of wing; a light puff of breath will illustrate this by hurling the helpless creature away, and it will not venture on the wing again for some time after finding a safe harbor. The prevalence of mosquitoes during a land breeze is easily explained. It is usually only during the lulls in the wind that Culex can fly. Generally on our coast a sea breeze means a stiff breeze, and during these mosquitoes will be found hovering on the leeward side of houses, sand dunes, and thick foliage.... While the strong breezes last, they will stick closely to these friendly shelters, though a cluster of houses may be but a few rods off, filled with unsuspecting mortals who imagine their tormentors are far inland over the salt meadows. But if the wind dies down, as it usually does when veering, out come swarms upon swarms of females intent upon satisfying their depraved taste for blood. This explains why they appear on the field of action almost immediately after the cessation of the strong breeze; on the supposition that they were blown inland, this sudden reappearance would be unaccountable."
A sultry, rainy period of midsummer is commonly referred to as "good mosquito weather." The accepted idea is that mosquitoes are much more abundant at such times. This is true, and the explanation is simple. Mosquito larvae, or wrigglers, as they are termed, require water for their development. A heavy shower leaves standing water, which, when the air is full of moisture, evaporates slowly. Then, too, the heat favors the growth of the microoerganisms on which the larvae feed; wrigglers found in the water forty-eight hours after their formation will have plenty of food, and adult mosquitoes will appear six to eight days after the eggs are laid. Clear weather, with quick evaporation, interferes with the development of the wrigglers, so that a season with plenty of rain, but with sunshiny, drying weather intervening, is not "good mosquito weather."
Destroy the Larvae
Inasmuch as a generation of mosquitoes appear to torment man within ten days, at the longest, after the eggs are laid; as a batch laid by a female mosquito contains from two hundred to four hundred eggs; as from each egg may issue a larva or wriggler which in six days will be an adult mosquito on the wing—it is to the destruction of the larvae that attention should be directed. The larva is a slender organism, white or gray in color, comprising eight segments. The last of these parts is in the form of a tube, through which the wriggler breathes. Although its habitat is the water, it must come to the surface to breathe, therefore its natural position is head down and tail, or respiratory tube, up. Now, if oil is spread on the surface of a pool inhabited by mosquito larvae, the wrigglers are denied access to the air which they must have. Therefore, they drown, just as any other air-breathing animal would drown under similar circumstances.
Best Preventive Measures
As to the best methods to employ in ridding a country place, or any other region, of mosquitoes, the directions furnished by Dr. L. O. Howard, the Government entomologist, who has been a careful student of the problem since 1867, are of great value:
"Altogether,[3] the most satisfactory ways of fighting mosquitoes are those which result in the destruction of the larvae or the abolition of their breeding places. In not every locality are these measures feasible, but in many places there is absolutely no necessity for the mosquito annoyance. The three main preventive measures are the draining of breeding places, the introduction of small fish into fishless breeding places, and the treatment of such pools with kerosene. These are three alternatives, any one of which will be efficacious and any one of which may be used where there are reasons against the trial of the others."
Quantity of Kerosene to be Used
"The quantity of kerosene to be practically used, as shown by the writer's experiments, is approximately one ounce to fifteen square feet of water surface, and ordinarily the application need not be renewed for one month.... The writer is now advising the use of the grade known as lubricating oil, as the result of the extensive experiments made on Staten Island. It is much more persistent than the ordinary illuminating oils.... On ponds of any size the quickest and most perfect method of forming a film of kerosene will be to spray the oil over the surface of the water.... It is not, however, the great sea marshes along the coast, where mosquitoes breed in countless numbers, which we can expect to treat by this method, but the inland places, where the mosquito supply is derived from comparatively small swamps and circumscribed pools. In most localities people endure the torment or direct their remedies against the adult insect only, without the slightest attempt to investigate the source of the supply, when the very first step should be the undertaking of such an investigation.
"The remedy which depends upon draining breeding places needs no extended discussion. Naturally the draining off of the water of pools will prevent mosquitoes from breeding there, and the possibility of such draining and the means by which it may be done will vary with each individual case. The writer is informed that an elaborate bit of work which has been done at Virginia Beach bears on this method. Behind the hotels at this place, the hotels themselves fronting upon the beach, was a large fresh-water lake, which, with its adjoining swamps, was a source of mosquito supply, and it was further feared that it made the neighborhood malarious. Two canals were cut from the lake to the ocean, and by means of machinery the water of the lake was changed from a body of fresh to a body of salt water. Water that is somewhat brackish will support mosquitoes, but water that is purely salt will destroy them."
Employing Fish to Destroy Larvae
"The introduction of fish into fishless breeding places is another matter. It may be undesirable to treat certain breeding places with kerosene, as, for instance, water which is intended for drinking, although this has been done without harm in tanks where, as is customary, the drinking supply is drawn from the bottom of the tank. The value of most small fishes for the purpose of destroying mosquito larvae was well indicated by an experience described to us by Mr. C. H. Russell, of Bridgeport, Conn. In this case a very high tide broke away a dike and flooded the salt meadows of Stratford, a small town a few miles from Bridgeport. The receding tide left two small lakes, nearly side by side and of the same size. In one lake the tide left a dozen or more small fishes, while the other was fishless. An examination by Mr. Russell in the summer of 1891 showed that while the fishless lake contained tens of thousands of mosquito larvae, that containing the fish had no larvae. The use of carp for this purpose has been demonstrated, but most small fish will answer as well. The writer knows of none that will be better than either of the common little sticklebacks (Gasterosteus aculeatus or Pygosteus pungitius)."
Is mosquito fighting a success? This question is an all-important one, not only to the summer resident, but also to cities and towns contiguous to salt-water marshes, or to swampy lands, well suited for mosquito breeding. The answer is this: Mosquito control is possible; actual extermination impossible with an insect that develops so rapidly. The "Jersey mosquito," the unscientific name popularly given to an insect of huge size and ravenous appetite, has become famous. As a matter of fact, the species of mosquitoes found in New Jersey are no more rare or varied than those found on Staten Island or on Long Island. But until very recently the region lying between Jersey City and Newark has been particularly favorable to the development of mosquito larvae. It has been announced in the press that mosquitoes have been driven out of the Newark meadows. This is an exaggeration, of course, but the work accomplished there is remarkable, and other infected regions may take heart from the marked success which has attended the efforts of Dr. John B. Smith, Entomologist of the New Jersey State Agricultural Experiment Station.
Remarkable Work Accomplished
The salt marsh lying within the limits of the city of Newark covers an area of about 3,500 acres. It extends from a point on the Passaic River to the mouth of Bound Creek, where it empties into Newark Bay. Its length is about eight miles and it has an extreme width of three miles. The Newark marsh problem was a very complex one. The meadows are cut into many sections by the several traversing railroads and by creeks; this materially influences the drainage. The Peddie Street sewer crosses the marsh in a straight line of about three miles from the city to the bay. This sewer is twenty feet wide, and its banks are from three to four feet above the marsh land. |
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