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SCIENTIFIC AMERICAN SUPPLEMENT NO. 514
NEW YORK, NOVEMBER 7, 1885
Scientific American Supplement. Vol. XX., No. 514.
Scientific American established 1845
Scientific American Supplement, $5 a year.
Scientific American and Supplement, $7 a year.
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TABLE OF CONTENTS.
I. CHEMISTRY.—Chlorides in the Rainfall of 1884. Apparatus for Evaporating Organic Liquids.—With description and 3 figures.
II. ENGINEERING AND MECHANICS.—Relative Costs of Fluid and Solid Fuels.
The Manufacture of Steel Castings.
Science in Diminishing Casualties at Sea.—Extract of a paper read before the British Association by DON ARTURO DE MARCOARTER.
Improved Leveling Machine. 9 figures.
The Span of Cabin John Bridge.
Improvements in Metal Wheels. 3 figures.
Apparatus for the Production of Water Gas. 3 figures.
III. TECHNOLOGY.—The Blue Print Process.—R.W. JONES.
Reproductions of Drawings in Blue Lines on White Ground.—By A.H. HAIG.
A Plan for a Carbonizing House.—With full description and 5 figures.
The Scholar's Compasses.
The Integraph.—With full description and engraving.
Apparatus for the Manufacture of Gaseous Beverages. 2 engravings.
Sandmann's Vinegar Apparatus. 1 figure.
Field Kitchens. 8 figures.
A New Cop Winding Machine. 3 figures.
The Preservation of Timber.—Report of the Committee of the American Society of Engineers.—The Boucherie process.—Experiments.—Decay of timber.
IV. PHYSICS, ELECTRICITY, LIGHT, ETC.—Apparatus for Measuring the Force of Explosives.—With engraving.
Lighting and Ventilating by Gas.—Advantages of gas over electricity, etc.—By WM. SUGG. 2 figures.
Ander's Telephone. 1 figure.
Brown's Electric Speed Regulator. 1 figure.
Magneto-electric Crossing Signal. 2 figures.
The Chromatoscope.—An aid to microscopy.
V. ART AND ARCHITECTURE.—The Barbara Uttmann Statue at Annaberg, Saxony.
Improvements in Concrete Construction.—Use of Portland cement.—System of building in concrete invented by Messrs. F. & J.P. West, London.
Albany Buildings. Southport.—An engraving.
VI. PHYSIOLOGY, HYGIENE, ETC.—The Sizes of Blood Corpuscles in Mammals and Birds.—A table.
The Absorption of Petroleum Ointment and Lard by the Skin.
VII. MISCELLANEOUS.—The Missing German Corvette Augusta.—With engraving.
The Tails of Comets.—The effect by a disturbance of solar waves, and not by special matter.
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ROMAN REMAINS AT LEICESTER, ENGLAND.
The Roman tessellated pavement in Jewry Wall Street, Leicester, discovered in the year 1832, is well known to archaeologists; it has also been known as difficult of access, and hardly to be seen in a dark cellar, and, in fact, it has not been seen or visited, except by very few persons. Some time ago the Town Council resolved to purchase the house and premises, with the object of preserving the pavement in situ, and of giving additional light and better access to it, and, this purchase having been completed in the beginning of the present year, the work of improvement began. It was now seen that the pavement was continuous under the premises of the adjoining house, and under the public street, and arrangements were at once made to uncover and annex these adjoining parts, so as to permit the whole to be seen at one view. The pavement thus uncovered forms a floor which, if complete, would measure 23 feet square; it lacks a part on the west side, and also the entire south border is missing. It is a marvel of constructive skill, of variety and beauty in form and color, and not the least part of the marvel arises from the almost beggarly elements out of which the designer has produced his truly harmonious effects. No squared, artificially colored, or glazed tesserae, such as we see in a modern floor, are used, but little pieces, irregularly but purposely formed of brick and stone. There are three shades of brick—a bright red, a dull or Indian red, and a shade between the two; slate from a neighboring quarry gives a dark bluish gray; an oolite supplies the warmer buff; and a fine white composition resembling limestone is used for the center points and borders. In addition, the outside border is formed with tesserae of rather larger size of a sage green limestone. Speaking generally, the design is formed by nine octagon figures, three by three, surrounded and divided by a guilloche cable band; the interspaces of the octagons are filled by four smaller square patterns, and the outer octagon spaces by 12 triangles. Outside these is a border formed by a cable band, by a second band of alternate heart-shaped, pear-shaped, and bell-shaped flowers, and by alternate white and gray bands; and outside all is the limestone border already described. This border is constructed with tesserae about five-eighths of an inch square. The remaining tesserae vary from one half to one-quarter inch of irregular rhomboidal form. The construction of the pavement is remarkable. There is a foundation of strong concrete below; over it is a bed of pounded brick and lime three to four inches thick, and upon this a layer of fine white cement, in which the tesserae are laid with their roughest side downward. Liquid cement appears to have been poured over the floor, filling up the interstices, after which the surface would be rubbed down and polished.
As to the probable date and occupation of the floor, it may be observed that the site of this pavement was near the center of the western Roman town. It is near the Jewry Wall, that is, near the military station and fortress. It was obviously the principal house in the place, and as clearly, therefore, the residence of the Praefectus, the local representative of the imperial power of Rome. The Roman occupation of the district began with the propraetorship of Ostorius Scapula, A.D. 50. He was succeeded in 59 by Suetonius Paulinus, who passed through Leicester from the Isle of Anglesea when the insurrection under Boadicea broke out. In the service of Suetonius was Julius Agricola, who was elected consul and governor of Britain about the year 70. He is commonly described as a wise and good governor, who introduced the arts of civilized life, taught the natives to build, and encouraged education. He left Britain about the year 85, and from that time to the decline of the Roman power is but about 300 years. We shall not be far from the truth, therefore, if we assign this work to the time or even to the personal influence of Agricola, 1,800 years ago.—London Times.
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Some time ago we published the fact that the Empress of Germany had offered a prize of $1,000 and the decoration of the Order of the Red Cross to the successful inventor of the best portable field hospital. Wm. M. Ducker, of No. 42 Fulton St., Brooklyn, sent in a design for competition. A few days ago Mr. Ducker received notice that his invention had won the prize. Another instance of the recognition of American genius abroad.
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THE BARBARA UTTMANN STATUE AT ANNABERG, SAXONY.
The question whether Barbara Uttmann, of Annaberg, Saxony, was the inventor of the art of making hand cushion lace, or only introduced it into Annaberg, in the Saxon mountains, has not yet been solved, notwithstanding the fact that the most rigid examinations have been made. It is the general belief, however, that she only introduced the art, having learned it from a foreigner in the year 1561. The person from whom she acquired this knowledge is said to have been a Protestant fugitive from Brabant, who was driven from her native land by the constables of the Inquisition, and who found a home in the Uttmann family. However, the probability is that what the fugitive showed Barbara Uttmann was the stitched, or embroidered, laces—points, so called—which are still manufactured in the Netherlands at the present time. It is very probable that the specimens shown induced Barbara Uttmann to invent the art of making lace by means of a hand cushion.
Very little is known of the family of Barbara Uttmann, which was originally from Nurnberg; but members of the same migrated to the Saxon mountains. Barbara's husband, Christof Uttmann, was the owner of extensive mines at Annaberg, and was very wealthy. She died at Annaberg, Jan. 14, 1584.
The art of making hand cushion lace was soon acquired by most of the residents in the Saxon mountains, which is a poor country, as the occupation of most of the inhabitants was mining, and it frequently happened that the wages were so low, and the means of sustaining life so expensive, that some other resource had to be found to make life more bearable. Barbara Uttmann's invention was thus a blessing to the country, and her name is held in high esteem. A monumental fountain is to be erected at Annaberg, and is to be surmounted by a statue of the country's benefactress, Barbara Uttmann. The statue, modeled by Robert Henze, is to be cast in bronze. It represents Barbara Uttmann in the costume worn at the time of the Reformation. She points to a piece of lace, which she has just completed, lying on the cushion, the shuttles being visible.
Some point, Valenciennes, and Guipure laces are made on a cushion by hand, with bobbins on which the thread is wound, the pins for giving the desired pattern to the lace being stuck into the cushion. A yard of hand cushion lace has been sold in England for as much as $25,000. The annexed cut, representing the Barbara Uttmann statue, was taken from the Illustrirte Zeitung.
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A Boston paper tells of a man who built two houses side by side, one for himself and one to sell. In the house sold he had placed a furnace against the party wall of the cellar, and from its hot air chamber he had constructed flues to heat his own domicile. The owner of the other house found it very hard to keep his own house warm, and was astounded at the amount of coal it took to render his family comfortable, while the "other fellow" kept himself warm at his neighbor's expense nearly a whole winter before the trick was discovered.
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IMPROVEMENTS IN CONCRETE CONSTRUCTION.
Portland cement concrete if made with a non-porous aggregate is impervious to moisture, and yet at the same time, if not hydraulically compressed, will take up a sufficient quantity of moisture from the air to prevent condensation upon the surface of the walls. It not only resists the disintegrating influences of the atmosphere, but becomes even harder with the lapse of time. It may also be made in several different colors, and can be finished off to nearly a polished surface or can be left quite rough. Walls built of this material may be made so hard that a nail cannot be driven into them, or they can be made sufficiently soft to become a fixing for joinery, and, if a non-porous aggregate be used, no damp course is required. Further than this, if land be bought upon which there is sufficient gravel, or even clay that can be burnt, the greatest portion of the building material may be obtained in excavating for the cellar; and in seaside localities, if the (salt) shingle from the beach be used, sound and dry walls will be obtained. The use of concrete as a material for building will be found to meet all the defects set forth by practical people, as it may be made fire-proof, vermin-proof, and nail-proof, and in dwellings for the poor will therefore resist the destructive efforts of the "young barbarian." Nothing, therefore, can be better as a building material. The system ordinarily employed to erect structures in concrete consists of first forming casings of wood, between which the liquid concrete is deposited, and allowed to become hard, or "to set." The casings are then removed, the cavities and other imperfections are filled in, and the wall receives a thin facing of a finer concrete. If mouldings or other ornament be required, they are applied to this face by the ordinary plasterer's methods. This system finds favor in engineering construction, and also in very simple forms of architectural work, but with very complicated work the waste in casings is very great. Besides this, however, the face is found sometimes to burst off, especially if it has been applied some time after the concrete forming the body of the wall has set, and the method of applying ornament is not economical.
A system of building in concrete has recently been invented by Messrs. F. & J.P. West, of London, illustrations of which we now present. To this system Messrs. West have given the name of "Concrete Exstruction," from the Latin "exstructio," which they consider to be a more appropriate word than "constructio," as applied to concrete building in general. In Messrs. West's system of building in concrete, instead of employing wood casings, between which to deposit the concrete or beton, and removing them when the beton has become hard, casings of concrete itself are employed. These casings are not removed when the beton has set, but they become a part of the wall and form a face to the work. In order to form the casings, the concrete is moulded in the form of slabs. Figs. 1 to 18 of our engravings show various forms of the slab, which may be manufactured with a surface of any dimensions and of rectangular (Fig. 1), triangular, hexagonal (Figs. 2, 14, and 15), and indeed of any other form that will make a complete surface, while for thickness it may be suited to the work to which it is to be applied, that used for heavy engineering work differing from that employed in house construction. It is found that the most convenient height for the rectangular slab (Fig. 1) is 12 inches and the breadth 18 inches, as the parts of a structure built with slabs of these dimensions more often correspond with architectural measurements. The hexagonal slab (Fig. 2) is made to measure 12 inches between its parallel sides. Where combinations of these slabs will not coincide with given dimensions, portions of slabs are moulded to supply the deficiency. The moulds in which the slabs are made are simple frames with linings having a thin face of India-rubber or other suitable material, by the use of which slabs with their edges as shown, and also of the greatest accuracy, can be manufactured. That portion of the back of the slab which is undercut is formed by means of soft India-rubber cores. The moulds for making portions of the slabs have a contrivance by which their length may be adjusted to suit given dimensions.
During the process of casting the slabs, and while they are in a plastic state, mouldings (if required) or other ornaments, having a suitable key, are inserted in the plastic surface, which is finished off to them (Figs. 7, 8, and 10). The slabs may also be cast with ornaments, etc., complete at one operation (Fig. 11), but it is more economical to have separate moulds for the mouldings and other ornaments, and separate moulds for the slabs, and to apply the mouldings, etc., during the process of casting the slab. Corbels (Fig. 9), sets off (which would be somewhat similar to the plinth course slab No. 10), and other constructive features may also be applied in a similar way, or may be provided for during the casting of the slab. A thin facing of marble or other ornamental solid or even plastic material may be applied to the face of the slabs during the process of casting, thus enabling the work to be finished as it is carried up, or a key may be formed on the face of the slab to enable the structure to be plastered afterward.
In Fig. 20, the structure from the bottom of the trenches is shown with the sides of the trenches removed. It will be seen that the footings are constructed in the most economical manner by not being stepped. As no damp-course is required in concrete work, when the aggregate is of a non-porous material, one is not shown. Upon the top of the footings is generally laid a horizontal slab, called the wall-base slab, the special feature of which is that it enables the thickness of the wall to be gauged accurately, and also provides a fixing for the first course of slabs. Figs. 4 and 5 show such slabs for internal and external angles, and Fig. 6 shows one for straight work. The use of a wall-base slab is not essential, although it is the more accurate method of building, for in cases where it is desirable to economize labor, or from other causes, the slabs forming the first course may be made with a thicker base, and may be fixed by a deposition of concrete, which is allowed to set behind them. The second course of slabs is laid upon the first course with breaking joints of half-slab bond, each course being keyed to the other by means of a quick-setting cementing material poured into the key-holes provided in the edges of the slab for that purpose, a bituminous cement being preferred. The key-holes are made in several ways, those shown in the illustrations being of a dovetail shape; circular, square, or indeed holes of any other shape formed in the edges of the slab and in an oblique direction are also employed. Special slabs for cants, or squint-quoins (Figs. 17 and 18) and angles (Figs. 12, 13, 14, 15, and 16) are manufactured, the angle occurring (if we omit the hexagonals and take the 18 inch slab) at three-quarters the length of each slab. This gives a half-slab bond to each course, as on one face of the quoin in one course will appear a quarter slab and in the course above a three-quarter slab superimposed upon it, or vice versa. Thus are the walls in Figs. 19 and 20 built up. For openings, the jambs and lintels (and in window-openings the sill) are made solid with a provision for a key-hole to the mass of concrete filling behind them. That portion of the jambs against which the slabs butt has a groove coinciding with a similar one in the edge of the slab, for the purpose of forming a joggle joint by squeezing the bedding material into them or by joggling them in with a cement grout. All the slabs are joggled together in a similar way.
The plastic concrete filling or beton which the shells are made to contain may be deposited between the slabs when any number of courses (according to convenience) have been built up, and when set practically forms with the solid work introduced a monolith, to which the face slabs are securely keyed. With over-clayed Portland cements, which are known to contract in setting, and with those over-limed cements which expand (both of which are not true Portland cements), the filling in is done in equal sections, with a vertical space equal to each section left between them until the first sections have become thoroughly hard, and these are then filled in at a second operation. In order to provide for flues, air-passages, and ways for electric installations, and for gas and water, pipes (made of an insulating material if required) or cores of the required shape are inserted in the plastic beton, and where necessary suitable openings are provided on the face of the work. Provision is also made for fixing joinery by inserting, where required, slabs made or partly made of a material into which nails may be driven, such as concrete made with an aggregate of burnt clay, coke, and such like. Hollow lintels are also made of the slabs keyed together at their vertical joints, and when in position these are filled in with beton. This system, however, is only recommended for fire-place openings instead of arches.
In Fig. 25, circular construction is exhibited as applied to the apsidal end of a church, slabs similar to those shown in Fig. 21 being employed for that purpose, while Figs. 22, 23, and 24 show forms of slabs suitable for constructing cylinders with horizontal axes and domes. In Fig. 19, which is the upper part of Fig. 20, is shown a system of constructing floors of these slabs. It is only necessary to explain that the slabs are first keyed to the lower flange of the iron joist by means of a cement (bituminous preferred), and the combination is then fixed in position, the edges of the slabs adhering to, or rather supported by, the iron joist being rebated so as to receive and support intervening slabs, the heading joints of which are laid to break with those of the slabs supported by the joists. For double floors the iron joists are made with a double flange on their lower edge, and are fitted to iron girders, which cross in the opposite direction. This provision secures the covering of the cross girders on their undersides by the ceiling slabs. The concrete having been deposited upon the slabs, its upper surface may be finished off in any of the usual ways, while the ceiling may be treated in any of the ways described for the walls. This system does not exclude the ordinary methods of constructing floors and roofs, although it supplies a fireproof system. Where required, bricks, stone, and, in fact, any other building material, may be used in conjunction with the slabs.
The system of building construction is intended, as in the case with all concrete, to supersede brickwork and masonry in the various uses to which they have been applied, and, at the same time, to offer a more perfect system of building in concrete. Hitherto slab concrete work has never been erected in a perfectly finished state (i.e., with mouldings, etc., complete), but has either been left in a rough state or without ornament, or else has been constructed so as never to be capable of receiving good ornamental treatment. Hitherto the great difficulty in constructing concrete walls of concrete and other slabs has been to prevent the slabs from being forced outward or from toppling over by the pressure of the plastic filling-in material from the time of its deposition between the slabs until it has become hard enough to form, with the slabs, a solid wall. Besides the system of forming the slabs of L (vertical or horizontal) section, or with a kind of internal buttress and shoring them up from the outside, or of supporting the slabs upon framing fixed against the faces of the wall, several devices have been used to obviate this difficulty.
In the first place, temporary ties, or gauges, connecting the slabs forming the two faces of the wall, have been used, and as soon as the plastic filling-in material has set or become hard (but not before), these have been removed. Secondly, permanent ties or cramps have been used, and, as their name implies, have been allowed to remain in the wall and to be entirely buried in the plastic filling-in material. These permanent transverse ties or cramps have been of two kinds: those which were affixed as soon as the slabs were placed in position, and those which were made to form part of the manufactured slab, as, for instance, slabs of Z or H horizontal section. Thirdly, a small layer of the plastic filling-in material itself has been made to act as a transverse tie by depositing it, when plastic, between the slabs forming the two parallel faces of each course, allowing it (before filling in the remaining part) to set and to thus connect together the slabs forming each face of the wall, a suitable hold on the slabs, in some cases, being given to the tie by a portion of the slab being undercut in some way, as by being dovetailed, etc. As the slabs in this latter system generally have wide bases, they may also be bedded or jointed in cement, and, provided temporary ties be placed across their upper edges to connect the slabs forming each face of the wall together, the space between the faces of the wall may then be filled in with the plastic concrete.
All these devices, however, are not of permanent utility; they are only temporarily required (i.e., up to the time that the beton has become hard and formed a permanent traverse tie between the two faces of the wall), for it is manifest that the ultimate object of all slab concrete construction is: (a) To retain and to mould the plastic concrete used in forming the wall; (b) to key or fix the slabs to the mass which they themselves have moulded; and (c) to form a facing to the wall. When these objects shall have been accomplished, there is no further need of any tie whatever beyond that which naturally obtains in a concrete wall. In West's system, however, where the slabs are keyed course to course, any kind of transverse tie to be used during the process of construction, except that used in the starting course, is entirely dispensed with, and the courses of slabs above depend solely upon the courses of slabs below them for their stability and rigidity up to the time that the plastic filling-in has been deposited and become hard between both faces of the wall.
There is, however, a more decided difference between West's system and those previously in use, for it is marked by the fact that the slabs composing the shell of the whole structure in many cases may be built up before the filling-in is deposited between the slabs, and in none of the other cases can this be done. In fact, only in the first two cases before mentioned can more than one course of slabs be laid before filling-in of some kind must be done. Compared with the ordinary method of building in concrete, this system avoids: 1. The charge for use and waste of wood casings; 2. finishing the face of the work (both inside and outside) after the structure is raised, and, therefore, the bursting-off of the finished face; and 3. the difficulties encountered in working mouldings and other ornaments on the face of the work by the ordinary plasterer's methods. It also provides a face of any of the usual colors that may be obtained in concrete, besides a facing of any other material, such as marble, etc., and produces better and more durable work, at the same time showing a saving in cost, especially in the better classes of work; all of which is effected with less plant than ordinarily required. For engineering work, such as sea walls, the hexagonal slabs, made of greater thickness than those employed for ordinary walling, will answer admirably, especially if the grooves be made proportionately larger. By the use of these slabs the work may be built up with great rapidity. For small domestic work, such as the dwellings of artisans, these slabs; which are of such a form as to render them easy of transport, may be supplied to the workmen themselves in order that they may erect their own dwellings, as, on account of the simplicity of this system and the absence of need of plant, any intelligent mechanic can do the work.
Any arrangement of independent scaffolding may be employed for this system, but that invented specially for the purpose by Mr. Frank West, as shown in Fig. 26 of our engravings, is to be preferred. It not only supplies the necessary scaffold, but also the necessary arrangements for hoisting the slabs, as well as for raising the liquid concrete and depositing it behind the slabs. It is really an independent scaffold, and may be used wherever a light tramway of contractor's rails can be laid, which in crowded thoroughfares would of necessity be upon a staging erected over the footway. The under frame is carried upon two bogie frames running upon the contractor's rail, by which means it is enabled to turn sharp curves, a guide plate inside the inner rail being provided at the curves for this purpose. The scaffold itself consists of a climbing platform made to travel up or down by means of four posts which have racks attached to their faces, and which are fixed to the under frame and securely braced to resist racking strains. A worm gearing, actuated by a wheel on the upper side of the scaffold, causes the scaffold to ascend or descend. A railgrip, made to act at the curves as well as on the straight portions of the rail by being attached to a radial arm fixed to the under frame, assists the stability of the scaffold where required, but the gauge of the rails is altered to render the scaffold more or less stable according to its height. Combined with the same machine, and traveling up and down one of the same posts used for the scaffold, is an improved crane. Its action depends upon the proposition in geometry that if the length of the base of a triangle be altered, its angles, and therefore its altitude, are altered. A portion of the vertical post up and down which the crane climbs forms the base of a triangle, and a portion of the jib, together with the stay, forms the remaining two sides. Hence, by causing the foot of one or the other to travel upward, by means of the worm gearing, the upper end of the jib is either elevated or depressed.
The concrete elevator, which is also combined with the scaffold, consists of a series of buckets carried upon two parallel endless chains passing over two pairs of wheels. On the under frame is fixed a hopper, into which is thrown, either by hand or from a concrete mixer running upon the rails, the material to be hoisted, and from which it gravitates into a narrow channel, through which pass the buckets (attached to the chain) with a shovel-like action. The buckets, a motor being applied to one pair of wheels, thus automatically fill themselves, and on arriving at top are made to tip their contents, and jar themselves, automatically into a hopper by means of a small pinion, keyed to the shaft by which they are attached to the endless chain, becoming engaged in a small rack fixed for that purpose. From the upper hopper the material is taken away to the required destination by means of a worm working in a tube. For varying heights, extra lengths of chain and buckets are inserted and secured by a bolt passed through each end link, and secured by a nut. By using this scaffold, a saving in plant, cartage, and labor is effected. The elevator may also be used for raising any other material besides concrete.
Such is the new system of concrete construction and scaffolding of Messrs. West, which appears to be based on sound and reasonable principles, and to have been thoughtfully and carefully worked out, and which moreover gives promise of success in the future. We may add in conclusion that specimens of the work and a model of a scaffold are shown by Messrs. West at their stand in the Inventions Exhibition.—Iron.
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THE BLUE PRINT PROCESS.
R.W. JONES.
1. Cover a flat board, the size of the drawing to be copied, with two or three thicknesses of common blanket or its equivalent.
2. Upon this place the prepared paper, sensitive side uppermost.
3. Press the tracing firmly and smoothly upon this paper, by means of a plate of clear glass, laid over both and clamped to the board.
4. Expose the whole—in a clear sunlight—from 4 to 6 minutes. In a winter's sun, from 6 to 10 minutes. In a clear sky, from 20 to 30 minutes.
5. Remove the prepared paper and pour clear water on it for one or two minutes, saturating it thoroughly, and hang up to dry.
The sensitive paper may be readily prepared, the only requisite quality in the paper itself being its ability to stand washing.
Cover the surface evenly with the following solution, using such a brush as is generally employed for the letter-press: 1 part soluble citrate of iron (or citrate of iron and ammonia), 1 part red prussiate of potash, and dissolve in 10 parts of water.
The solution must be kept carefully protected from light, and better results are obtained by not mixing the ingredients until immediately required. After being coated with the solution, the paper must be laid away to dry in a dark place, and must be shielded entirely from light until used. When dry, the paper is of a yellow and bronze color. After exposure the surface becomes darker, with the lines of the tracing still darker. Upon washing, the characteristic blue tint appears, with the lines of the tracing in vivid contrast. Excellent results have been obtained from glass negatives by this process.—Proc. Eng. Club, Phila.
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REPRODUCTION OF DRAWINGS IN BLUE LINES ON WHITE GROUND.
A.H. HAIG.
The following process for making photographic copies of drawings in blue lines on white background was invented by H. Pellet, and is based on the property of perchloride of iron of being converted into protochloride on exposure to light. Prussiate of potash when brought into contact with the perchloride of iron immediately turns the latter blue, but it does not affect the protochloride.
A bath is first prepared consisting of ten parts perchloride of iron, five parts oxalic or some other vegetable acid, and one hundred parts water. Should the paper to be used not be sufficiently sized, dextrine, gelatine, isinglass, or some similar substance must be added to the solution. The paper is sensitized by dipping in this solution and then dried in the dark, and may be kept for some length of time. To take a copy of a drawing made on cloth or transparent paper, it is laid on a sheet of the sensitive paper, and exposed to light in a printing frame or under a sheet of glass. The length of exposure varies with the state of the weather from 15 to 30 seconds in summer to from 40 to 70 seconds in winter, in full sunlight. In the shade, in clear weather, 2 to 6 minutes, and in cloudy weather, 15 to 40 minutes may be necessary. The printing may also be done by electric light. The print is now immersed in a bath consisting of 15 to 18 parts of prussiate of potash per 100 parts of water. Those parts protected from the light by the lines of the drawing immediately turn blue, while the rest of the paper, where the coating has been converted into protochloride by the effects of light, will remain white. Next, the image is freely washed in water, and then passed through a bath consisting of 8 to 10 parts of hydrochloric acid to 100 parts of water, for the purpose of removing protoxide of iron salt.
It is now again washed well in clean water and finally dried, when the drawing will appear in blue on a white background.—Proc. Eng. Club, Phila.
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[PROCEEDINGS OF THE ENGINEERS' CLUB OF PHILADELPHIA.]
RELATIVE COSTS OF FLUID AND SOLID FUELS.
[Footnote: Read June 20, 1885.]
By JAMES BEATTY, JR., Member of the Club.
During the past twenty-five years there have been numerous efforts to introduce fluid fuels as substitutes for coal, for the evaporation of water in boilers, metallurgical operations, and, on a small scale, for domestic purposes.
The advantages claimed for these fuels are: Reduction in the number of stokers, one man being able to do the work of four using solid fuel. Reduction in weight, amounting to one-half with the better classes. Reduction in bulk; for petroleum amounting to about thirty-six per cent., and with the gases, depending on the amount of compression. Ease of kindling and extinguishing fires, and of regulation of temperature. Almost perfect combustion and cleanliness.
Siemens used gas, distilled from coal and burnt in his well known regenerative furnace.
Deville experimented with petroleum on two locomotives running on the Paris and Strassburg Railroad.
Selwyn experimented with creosote in a small steam yacht, and under the boilers of steamship Oberlin.
Holland experimented with water-gas in the furnace of a locomotive running on the Long Island Railroad.
Isherwood experimented with petroleum under the boilers of United States steamers.
Three railroads in Russia are using naphtha in their locomotives, and steamers on the Volga are using the same fuel.
Wurtz experimented with crude petroleum in a reheating furnace at Jersey City.
Dowson, Strong, Lowe, and others have devised systems for the production of water gas.
These experiments, in general, have produced excellent results when considered merely in the light of heat production, but, in advocating their systems, the inventors seem to have overlooked the all-important item of cost.
It is the object of this paper to show the impracticability of such systems when considered from a commercial standpoint, so long as the supply of coal lasts, and prices keep within reasonable limits.
In many cases, authors on the subject have given purely theoretical results, without allowing for losses in the furnace.
The fuels to be considered are anthracite and bituminous coals, crude petroleum, and coal, generator and water gases.
The average compositions of these fuels (considering only the heating agents), as deduced from the analysis of eminent chemists, are:
PERCENTAGE BY WEIGHT.
__________ C H O CO CH_{4} C_{2}H_{4} - - Anthracite 87.7 3.3 3.2 Bituminous 80.8 5.0 8.2 Petroleum 84.8 13.1 1.5 Coal gas 6.5 14.3 52.4 14.8 Generator gas 1.98 35.5 1.46 Water gas 6.3 0.6 87.8 1.2 - -
We will employ the formula of Dulong—
h = 14,500 C + 62,000 (H - O/8)
to compute the theoretical heating powers of these fuels. In the case of methane, CH_{4}, the formula is not true, but the error is not great enough to seriously affect the result. This gives for the combustion of one pound of:
Anthracite 14,500 Br. Heat Units. Bituminous 14,200 " " " Petroleum 20,300 " " " Coal gas 20,200 " " " Generator gas 3,100 " " " Water gas 8,500 " " "
Reducing the above to terms of pounds of water evaporated from 212 deg. F., we have:
POUNDS OF WATER EVAPORATED FROM 212 deg. F.
Anthracite 15.023 Bituminous 14.69 Petroleum 21.00 Coal gas 20.87 Generator gas 3.21 Water gas 8.7
The results of experiments show the efficiency of fluid-burning furnaces to be about ninety per cent., while with coal sixty per cent. may be taken as a good figure. The great difference in the efficiencies is due to the fact that fluid fuels require for combustion very little air above the theoretical quantity, while with the solid fuels fully twice the theoretical quantity must be admitted to dilute the products of combustion.
Correcting our previous results for these efficiencies, we have:
POUNDS OF WATER ACTUALLY EVAPORATED FROM 212 deg. F., PER POUND OF FUEL.
Anthracite 9.0 Bituminous 8.8 Petroleum 18.9 Coal gas 18.8 Generator gas 2.9 Water gas 7.8
These figures agree closely with the results of experiments.
We will now consider the subject of cost.
The following cities have been selected, as manufacturing centers, termini of railroads, or fueling ports for steamers.
In the case of petroleum, as it is rarely shipped in the crude state, an approximation is made by adding to the cost at the nearest shipping port the freight charged on refined petroleum, and ten per cent. to cover duties and other charges.
Owing to the difficulty of obtaining prices, in some of the cities, there may be some errors.
COSTS. MARCH, 1884.
Anthracite Bituminous Coal gas per ton of per ton of per 1,000 2,240 lb. 2,240 lb. cubic feet.
New York $4 00 $4 25 $1 75 Chicago 5 00 3 50 1 25 New Orleans 6 00 3 50 3 00 San Francisco 12 00 7 50 3 00 London 5 00 3 00 0 75 Port Natal 12 50 11 00 Sydney 12 00 7 00 Valpariso 11 50 7 50
Generator Crude Water gas gas per 1,000 Petroleum per per 1,000 cubic feet. bbl. of 42 gal. cubic feet.
New York $0 45 $1 80 $0 50 Chicago 45 2 00 50 New Orleans 45 2 50 60 San Francisco 55 2 00 60 London 43 2 70 45 Port Natal Ap- 4 00 Ap- Sydney proxi- 4 50 proxi- Valparaiso mation. 3 00 mation.
In calculating the following table the specific gravity of coal gas is taken at 0.4; generator gas at 0.44; water gas at 0.48; petroleum, 0.8.
POUNDS OF FUEL FOR $1.00. MARCH, 1884.
Anthracite. Bituminous. Petroleum. Coal Water Generator gas gas. gas.
New York 560 527 156 18 74 76 Chicago 448 640 142 24 74 76 New Orleans 374 640 114 10 74 76 San Francisco 187 299 142 10 62 62 London 448 747 104 40 82 79 Port Natal 179 204 71 Ap- Ap- Sydney 187 320 63 proxi- proxi- Valparaiso 195 299 94 mate. mate.
These figures, multiplied by the actual evaporative powers as calculated, give:
POUNDS OF WATER EVAPORATED FROM 212 deg. F. FOR $1.
Anthracite. Bituminous. Petroleum. Coal Generator Water gas gas. gas.
New York 5040 4643 2948 338 220 577 Chicago 4032 5638 2684 451 220 577 New Orleans 3366 5638 2155 188 220 577 San Francisco 1683 2634 2684 188 179 484 London 4032 6581 1966 751 228 640 Port Natal 1611 1797 1342 Ap- Ap- Sydney 1683 2819 1191 proxi- proxi- Valparaiso 1755 2634 1776 mate. mate.
RELATIVE COSTS.
Anthracite. Bituminous. Petroleum. Coal Generator Water gas gas. gas.
New York $1 00 $1 08 $1 71 $14 92 $22 90 $8 70 Chicago 1 00 71 1 50 8 72 18 30 7 00 New Orleans 1 00 59 1 56 17 90 15 30 5 80 San Francisco 1 00 64 1 50 8 75 9 40 3 50 London 1 00 61 2 05 7 16 17 70 6 30 Port Natal 1 00 90 1 21 Sydney 1 00 34 1 39 Valparaiso 1 00 44 1 03
These figures are very much against the fluid fuels, but there may be circumstances in which the benefits to be derived from their use will exceed the additional cost. It is difficult to make a comparison without considering particular cases, but for intermittent heating petroleum would probably be more economical, though for a steady fire coal holds its own.
* * * * *
THE MANUFACTURE OF STEEL CASTINGS.
At the opening meeting for the winter session of the Iron and Steel Works Managers' Institute, held at Dudley on September 12, Mr. R. Smith-Casson in the chair, Mr. B.F. McCallem, of Glasgow, read a paper on "Steel Castings," which developed an interesting discussion upon steel casting practice. Mr. McCallem said that it was thirty years since the first crucible steel castings were made in Sheffield in the general way, and with one exception the method of manufacture was pretty much the same now as at that early date. The improvement was the employment of gas furnaces instead of the old coke holes for melting. Important economies had resulted from this introduction. Where before it required 3 tons of coke to melt 1 ton of steel, the same thing was now done with 35 cwt. of very poor slack. Though it was apparently easy to make crucible steel castings, it was not in reality easy to make a true steel, that was to say, to make a metal that contained only the correct proportions of carbon and silicon and manganese. The only real way to make crucible castings of true steel was to melt the proper proportions of cast steel scrap with the proper amounts of silicon and manganese to produce that chemical composition which was known to be necessary in best castings. It was in consequence of this difficulty that many makers resorted to the addition of hematite pigs. The Bessemer process was used much more extensively upon the Continent than in this country in the manufacture of castings. It seemed likely that Mr. Allen's agitator for agitating the steel in the ladle so as to remove the gases would be taken up largely for open-hearth castings and open-hearth mild steel, as it had a wonderful effect. The Wilson gas producer, working in conjunction with the open-hearth furnace, had recently produced some extremely wonderful results. In some large works, steel was by its aid being melted from slack which was previously absolutely a waste product. The method of making open-hearth steel castings might be varied greatly. The ordinary method generally practiced in this country was a modification of the Terre Noire process. The moulds employed were only of secondary importance to the making of the steel itself. Unless the mould was good, no matter how good the steel was, the casing was spoiled. The best composition which had been found for moulds was that of a large firm in Sheffield, but unfortunately it was rather expensive. A good steel casting ought to contain about 0.3 per cent. carbon and 0.3 per cent. of silicon and from 0.6 to 1 per cent. of manganese. Such a casting, if free from other impurities, would have a strength of between 30 and 40 tons, and on an 8 inch specimen would give an elongation of 20 per cent. or even more. It was possible by the Terre Noire process to produce by casting as good a piece of steel as could be made by any amount of rolling and hammering.
The chairman said that, as they had so high an authority as Mr. McCallem present, Staffordshire men would like to know his opinion upon the open hearth basic system, in which they were greatly interested.
Mr. McCallem said that he believed that the basic process would be worked successfully in this country in the open-hearth furnace before it would be in the converter. At the Brymbo Works, in Wales, he had seen the basic process worked very successfully in the open-hearth furnace; and he was recently informed by the manager that he was producing ingots at the remarkably low sum of 65s. per ton.
The chairman said that some samples which had been sent into Staffordshire from Brymbo for rolling into sheets had behaved admirably. He thought that the Patent Shaft and Axletree Company, at Wednesbury, were at the present moment putting down an open-hearth furnace on the basic process.
The discussion was continued with considerable vigor by Messrs. H. Fisher (vice-president), James Rigby, J. Tibbs, M. Millard, Walker, W. Yeomans (secretary), and others. Several of these gave it as their experience that the best castings contained the most blowholes, and Mr. McCallem accepted the pronouncement, with some slight qualification.
* * * * *
SCIENCE IN DIMINISHING CASUALTIES AT SEA.
At the recent meeting of the British Association, Don Arturo de Marcoartu read a paper on the above subject.
He stated that he wished to draw special attention to increasing the safety of navigation against storms, fogs, fire, and collisions with wrecks, icebergs, or vessels, and recommending the development of maritime telegraphy. He urged that vessels should be supplied with apparatus to communicate with and telegraph to each other and to the nearest coast the weather and sea passed over by them, and that reports given by vessels should be used as "warnings" more extensively. He wished the mid-Atlantic stations connected by telegraph for the same purpose.
In regard to the use of oil on rough seas, he said that Dr. Badeley in 1857, Mr. John Shields five years ago at Peterhead and last year at Folkestone, the Board of Trade in 1883, and a committee on life saving appliances of the United States had made experiments. The conclusions of the committee were that in deep water oil had a calming effect upon a rough sea, but there was nothing in either source of information which yet answered the question whether or not there is in the force exerted by the wind a point beyond which oil cannot counteract its influence in causing the sea to break. He thought it appeared that oil had some utility on tidal bars; on wrecks, to facilitate the operations of rescue; on lifeboats and on lifebuoys. In regard to icebergs, he thought the possibility of obtaining an echo from an iceberg when in dangerous proximity to a ship should be tried. He advocated the use of automatic sprinklers in the case of fire, the establishment of parabolic reflectors for concentration of sound, and the further prosecution of experiments by Professor Bell in establishing communication between vessels some distance apart by means of interrupted electrical currents. The improvement of navigation, he said, meant an international code of police to improve police rules of navigation; an international code of universal telegraphy for navigation; an international office of meteorology and navigation to collect the studies; experiments on the weather, on the sea, on the casualties; and the discovery by experiment of new apparatus and appliances to diminish maritime disaster.
He had called the attention of two governments to this matter, and he hoped that before long there would be proposed an international congress—such as the postal, telegraph, and sanitary congresses, and the international convention to fix the common meridian—by one of the maritime powers, by which would be founded an international institution to diminish casualties at sea. He recommended a universal system of buoys. The great losses of life and property every year were worthy the devotion of L300,000 by an international institution, which would be much less than the monthly average loss in navigation.
Admiral Pim said that ships were improperly built—some were ten times longer than their beam. There was nothing in the world so ticklish as a ship; touch her in the waist, and down she goes. He believed sailing ships ought not to exceed four times their beam, and steamers certainly not more than six times. He pointed out that a fruitful cause of accidents was the stopping of steaming all at once in the case of impending collision, by which the rudder lost control of the vessel. If constructors looked more to the form of the ships, and got them to steer better, collisions would be avoided.
The Lord Advocate said it had always occurred to him that one great secret of collisions at sea was the present system of lights, which made it impossible for the vessel at once to inform another vessel what it was about. The method of signaling was very crude, and he ventured to say that it was quite out of date when vessels met each other at a rate of speed of 24 to 25 knots. He had, as an amateur, tried a method which he would attempt to explain. His idea was to fit up a lantern on deck, showing an electric light. The instrument would be controlled by the rudder, and the commanding officer of the vessel would be able so to turn it when the helm was put up or down that the light would flash at some distance in front of either bow of the vessel, and thus be a signal to a vessel coming in an opposite direction. When the helm was amidships, the light was shown straight ahead, and could not be moved until the helm was shifted. The direction in which the vessel was going could not by any possibility be mistaken, and it was plain that if the lights from two ships crossed each other, then there was danger. If the lights were clear of each other, then the ships would pass safely.
Sir James Douglass asked if his Lordship had made any experiments.
The Lord Advocate said he had not. The Board of Trade had such a number of inventions on this subject on hand that he supposed they were already disgusted. Besides, he was only an amateur, and left the carrying out of the suggestion to others.
Sir James Douglass said this idea of a lantern did very well for a short distance, but for a long distance it utterly failed. It was very difficult to realize a movement from a distance of over a mile out to sea, and signals were required to be visible for from two to three miles.
The Lord Advocate said his idea depended not upon the object light, but upon the sweep of the light on the water.
Sir James Douglass said all those questions were of the utmost importance to a maritime country. In regard to experiments with oil on troubled water, he had witnessed them, and he had carefully studied all the reports, and had come to the conclusion that they were all very well in a tub of water or a pond, but on the ocean they were utterly hopeless. He would stake his reputation on that. They had been tried in the neighborhood of Aberdeen, and he had prophesied the results before they were commenced. It was utterly hopeless to think that a quantity of oil had the power of laying a storm—all the world could not produce oil enough to bring about that result.
There might be something in maritime telegraphy, and he hoped the experiments of Mr. Graham Bell, in transmitting through two or three mile distances, would come to something. He did not believe in powerful lights. Increase the lights to any very great extent, and a dazzling effect was the result. In regard to sound, he wondered that no more effective alarm was used than the whistle. It was well known that, as the whistle instrument was enlarged, the sound became more and more a roar. He would have ships use all their boiler power in sounding a siren, so that the sound could be heard at a distance of not less than two or three miles in any weather. With such a signal as that there ought to be, not absolute safety, but collisions would be more easily prevented. He was glad to say that a universal system of buoys had been practically arranged, thanks to the Duke of Edinburgh and his committee, so that, as soon as an old system can be changed to a new one, all the buoys would bear one universal language.
Admiral Pim pointed out that a red light would show four miles, while a green light was only visible for two miles and a half, so that, if a green light were seen, it indicated that the two vessels were within two miles and a half of each other.
Sir James Douglass said there was undoubtedly a weakness in regard to these lights; and he held that in the manufacture of lights effect should be given to the difference that existed in the various lights, so that, by making the green light more powerful, it could penetrate as far as the red, and in the same way making the red and green lights proportionately more powerful, so that they would penetrate as far as the white light.
Sir James Douglass said he had seen a parabolic reflector for sound tried, but, unfortunately, the reflector so intensified and focused all the sounds about the vessel and the noise of the sea that the operator could hear nothing but a chaos of sound.
* * * * *
A PLAN FOR A CARBONIZING HOUSE.
The operation of carbonizing woolen rags for the purpose of obtaining pure wool, through the destruction of the vegetable substances contained in the raw material, maybe divided into two parts, viz., the immersion of the rags in acid, with subsequent washing and drying, and the carbonization properly so called. The first part is so well known, and is so simple in its details and apparatus, that it is useless to dwell upon it in this place. But the second requires more scientific arrangements than those that seem to be generally adopted, and, as carbonization is now tending to constitute a special industry, we think it is of interest to give here a typical plan for a plant of this kind. It will be remarked that this plan contains all the parts in duplicate. The object of this arrangement is to permit of a greater production, by rendering the operation continuous through half of the apparatus being in operation while the other half is being emptied and filled.
Figs. 4 and 5 give plans of the ground floor and first story, and Figs. 1, 2, and 3 give vertical sections. The second story is arranged like the first, and serves as a drier. As we have said, there is a double series of chambers for carbonization, drying, and work generally. These two series are arranged on each side of a central portion, which contains the heating and ventilating apparatus and a stone stairway giving access to the upper stories. The heating apparatus is a hot air stove provided with a system of piping. The rags to be carbonized or the wool to be dried are placed upon wire cloth frames.
The carbonization is effected in the following way: When the heating apparatus has been fired up, and has been operating for about half an hour, the apertures, i, are opened so as to let the air in, as are also those, m, which allow the hot air to pass into the chambers. The hot air then descends from the top of the chamber into the wool or rags, and, becoming saturated and heavier, descends and makes its exit from the chamber through an aperture, n, near the floor, whence it flows to the central chimney. This latter, which is built of brick or stone, contains in its center a second chimney (formed of cast or forged iron pipes) that serves to carry off into the atmosphere the products of combustion from the heating apparatus. The heat that radiates from these pipes serves at the same time to heat the annular space through which the vapors derived from the wool are disengaged.
The air, heated to 40 deg. or 50 deg., is made to pass thus for several hours, until the greater part of the humidity has been removed. The temperature is then raised to 80 deg. or 90 deg. by gradually closing the apertures that give access to the ventilating chimney. In order that it may be possible to further increase the temperature during the last hour, and raise it to 90 deg. or 120 deg., an arrangement is provided that prevents all entrance of the external air into the heating apparatus, and that replaces such air with the hot air of the chamber; so that this hot air circulates in the pipes of the stove and thus becomes gradually hotter and hotter. The hot vapors that issue from the lower chamber rise into the upper one, where they are used for the preliminary drying of another part of the materials.
The hot air stove should be well lined with refractory clay, in order to prevent the iron from getting red hot, and the grate should be of relatively wide surface. All the pipes should be of cast iron, and all the joints be well turned. Every neglect to see to such matters, with a view to saving money, will surely lead in the long run to bad results.
The mode of work indicated here is called the moist process. It necessitates the use of a solution of sulphuric acid, but, as this latter destroys most colors, it cannot be used when it is desired to preserve the tint of the woolen under treatment. In this case recourse is had to the dry process, which consists in substituting the vapors of nitric acid heated to 115 deg. or 125 deg. for the sulphuric acid. The arrangement of the rooms must likewise be different. The chambers, which may be in duplicate, as in the preceding case, are vaulted, and are about three yards long by three wide and three high. The rags are put into wire cages that have six divisions, and that are located in the middle of the chamber, where they are slowly revolved by means of gearings. Under the floor are the heating flues, and upon it is a reservoir for holding the vessel that contains the acid to be vaporized. The arrangements for the admission of air and carrying along the vapors are the same as in the other case. Great precaution should be taken to have the flues so constructed as to prevent fire.—Bull, de la Musee de l'Industrie.
* * * * *
APPARATUS FOR EVAPORATING ORGANIC LIQUIDS.
According to Mr. D'A. Bernard, it is especially important, in the dry distillation of distiller's wash in a closed vessel, for the production of methyls, ammonia, acetates, and methylamine, that the mass shall be divided as completely as possible, since it then takes but a relatively moderate heat to completely destroy the organic coloring matter contained in the wash. The apparatus shown in Figs. 1 and 2 is based upon this observation.
The wash enters, through the hopper, D, and the valve, z, a long boiler, B, which is heated by the furnace, F, through the intermedium of a waterbath, w. An agitator, E, moves the mass slowly to the other extremity of the boiler, from whence it makes its exit in the form of dust. To the frame, E, are fixed the scrapers, b, and the interrupted pieces, a, in front of which are the hinged valves, c. In the motion of the pieces, a, from right to left, these valves free the apertures thereof and allow the wash to pass, while in the motion from left to right the apertures are closed and the valves push the mass to be evaporated before them.
From any motor whatever, the frame, E, receives a double to and fro motion in a horizontal and vertical direction, the latter of which is produced by the rods, f, which are provided at their lower, forked extremity with rollers, e, over which passes the piece, d, that supports the frame, E. At their upper part the rods, f, pass through the side of the boiler, through the intermedium of stuffing boxes, and are connected by their upper extremities, through a link, with levers, g, that revolve around the point, h. A cam shaft, M, communicates a temporary, alternately rising and descending motion to the levers, g, and the rods f. The same shaft, M, opens and closes the valve, z, of the hopper, D, and thus regulates the entrance of the wash into the boiler. The frame, E, receives its horizontal to and fro motion from the rod, l, which traverses a stuffing-box and is moved by a crank on an eccentric, m. The material in powder derived from the evaporation of the wash is stored at the extremity of the apparatus into a lixiviating vessel, G, provided with a stirrer, H. The salts and other analogous matters are dissolved, and the residuum, which constitutes a carbonaceous mass, is forced out of the apparatus, while the solution passes directly to the refinery, where it is evaporated.
In manufactories where no refining is done, the crude potassa in powder is pushed on to a prolongation of the apparatus which is cooled by means of water, and is removed from time to time with shovels by the workmen, so that the orifice of the boiler remains constantly covered externally by the mass, and that the air cannot re-enter the apparatus.
The gases disengaged during the operation pass into a cooler, where they condense into a liquid which contains ammonia and methylamine. The non-condensable part of the gases is burned in the furnace of the manufactory.
* * * * *
IMPROVED LEVELING MACHINE.
In the American Court of the Inventions Exhibition, London, we find a leveling machine for sheet metals exhibited by Mr. J.W. Britton, of Cleveland, Ohio, and which we illustrate.
This apparatus is intended to supersede the cold rolling of plates in order to take the buckle out of them. The sheets are clamped in the jaws or grips shown, and the stretch is effected by means of a hydraulic ram connected directly to the nearest pair of jaws. The power is obtained by means of a pair of pumps run through spur-gearing by the belt pulleys shown. The action of the machine puts a strain on those parts of the plates which are not "bagged" or buckled, and this causes the surface to extend, the slack parts of the plate not being subject to the same stretching action. The machine shown is designed to operate on sheet iron from No. 7 to No. 30 gauge, and up to 36 in. wide, the limit for length being 120 in. About a dozen sheets can be operated on at once. The machine appears to have met with considerable success in America, and has been used for mild steel, iron, galvanized or tinned sheets, copper, brass, and zinc. The details of this machine are given in Figs. 1 to 8. Figs. 1 and 2 are a plan and side elevation of the bed of the machine, showing the position of the hydraulic ram. Fig. 3 shows the bars used for holding the back jaws in position, with the holes for adjusting to different lengths of the plates. Fig. 4 is a back view and section of the crosshead and one of the bolts that connect the moving grip with the hydraulic ram. Fig. 5 gives a plan and cross section of the back grip, and Fig. 6 is a back elevation of the same, with a front view and section of the gripping part. Fig. 7 shows the gear by which the jaws are opened and closed.
* * * * *
THE SCHOLAR'S COMPASSES.
Among the numerous arrangements that have been devised for drawing circles in diagrams, sketches, etc., one of the simplest is doubtless that which is represented in the accompanying figure, and which is known in England as the "scholar's compasses." It consists of a socket into which slides a pencil by hard friction, and to which is hinged a tapering, pointed leg. This latter and the pencil are held at the proper distance apart by means of a slotted strip of metal and a binding screw. When the instrument is closed, as shown in the figure to the left, it takes up but little space, and may be easily carried in the pocket without the point tearing the clothing, as the binding screw holds the leg firmly against the pencil.
The mode of using the apparatus is so well shown in the figure to the right that it is unnecessary to enter into any explanation.—La Nature.
* * * * *
THE INTEGRAPH.
In scientific researches in the domain of physics we often meet with the following problem: Being given any function whatever, y = f(x), to find a curve whose equation shall be
/ y = f(x)dx + C. /
[TEX: y = int f(x) dx + C.]
Let us take an example that touches us more closely; let us suppose that we know an induced current, and that we can represent it by a curve y=f(x). The question is to find the inductive current, that is to say, the curve represented by the equation
/ y = f(x)dx + C. /
[TEX: y = int f(x) dx + C.]
The apparatus called an integraph, constructed by Messrs. Napoli and Abdank-Abakanowicz, is designed for solving this problem mechanically, by tracing the curve sought. Let us take another example from the domain of electricity, in order to better show the utility of the apparatus; let us suppose that we have a curve representing the discharge of a pile or of an accumulator. The abscisses represent the times, and the ordinates the amperes. The question is to know at every moment the quantity of coulombs produced by the pile. The apparatus traces a curve whose ordinates give the number of coulombs sought. We might find a large number of analogous applications.
The apparatus is represented in the accompanying figure. An iron ruler, I, parallel with the axis of the X's, is fixed upon a drawing-board, and is provided with a longitudinal groove in its upper surface. In this groove move two rollers, which, in the center of the piece that connects them, carry two brass T-squares that are parallel with each other and at right angles with the first, or parallel with the axis of the Y's. Between these two rulers move two carriages, the first of which (nearest the axis of the X's) carries a point, A, designed to follow the contour of the curve to be integrated, while the second, which is placed further away, is provided at the center with a drawing-pen, A', whose point is guided by two equidistant wheels, R, R', that roll over the paper in such a way as to have their plane parallel with a given straight line, and that have always a direction such that the tangent of the point's angle with the axes of the X's is constantly proportional to the ordinate of the primitive curve.
The carriages are rendered very movable by substituting rolling for a sliding friction of the axes. To this effect, the extremities of the axes of the wheels that support and guide them are made thin, and roll over the plane surface of recesses formed for the purpose in the lateral steel surfaces of the carriages, while the circumference of the wheels rolls in grooves along the two T-squares.
These latter are, on the one hand, carried by rollers that run in the groove of the iron, I, and, on the other, by a single roller that runs over the paper. At right angles with one of these bars is fixed a divided ruler, through one point of which continually passes a third ruler, whose extremity pivots upon the point, A, of the first carriage.
When the divided ruler is placed upon the axis of the X's, and the point, A, of this carriage is following the contours of the figure to be integrated, the tangent of the angle made by the inclined ruler with the axis of the X's will be proportional to the ordinate of the figure. The wheels, R and R', of the drawing-pen, A', of the second carriage must move parallel with this ruler. In order to obtain such parallelism, we employ a parallelogram formed as follows: Two gear-wheels of the same diameter are fixed upon the ruler that ends at the point, A, of the first carriage, and their line of centers is parallel with the latter. The second carriage likewise carries two drums equal in diameter to those of the toothed wheels. These are fixed, and their line of centers must remain constantly parallel with the line of centers of the gear-wheels, and consequently with the straight line which passes through the point, A. This parallelism is obtained by means of a weak steel spring, or of a silken thread passing over the four wheels, the two first of which (the gear-wheels) hold it taut by means of a barrel and spring placed in the center of one of them.
The edge of the wheels, R, R', of the second carriage prevents the latter from giving way to the traction of the threads, permitting it thus to move only in the direction of their plane.
It will be seen that by this system two of the sides of the parallelogram are capable of elongating or contracting through the unwinding and winding of the silken thread on the drums of the two cog wheels, which latter, gearing with each other, allow of the escape of but the same length of the two threads.
It will be observed that in this system integration is effected by forcing the pen to follow a certain direction, and that consequently the curve does not depend upon the dimensions of the different parts of the apparatus.—La Lumiere Electrique.
* * * * *
APPARATUS FOR MANUFACTURING GASEOUS BEVERAGES.
The apparatus represented in the accompanying cuts is designed for the manufacture of gaseous beverages, and is of Messrs. Boulet & Co.'s make. Fig. 1 represents the apparatus complete, with gasometer and bottling machine. Fig. 2 gives a vertical section of the apparatus properly so called, including the producer, the purifier, and the saturator, all grouped upon a cast-iron column.
The producer, A, is designed to receive the sulphuric acid and carbonate of lime. A mixer, F, revolves in the interior of this, and effects an intimate admixture of the lime and acid without the necessity of the former being pulverized beforehand. The carbonate of lime (usually in the form of chalk) is introduced directly into the producer through the aperture, K, while the acid contained in the receptacle, B, at the side of the column and above the producer flows put through a curved pipe in the bottom. The flow is regulated by the valve, C. The receptacle, B, is lined with platinum. As soon as the acid comes into contact with the carbonate, there occurs a disengagement of carbonic acid gas, which flows directly through the pipe, F, into the purifier at the upper part of the column. From thence the gas passes into a third washer, D, of glass. When thoroughly washed, it flows through the pipe, L, into the gasometer, which is of galvanized iron, and is very carefully balanced.
The saturator, which is the most important part of the apparatus, comprises a pump, a feed reservoir, and a sphere. The pump, which is of bronze, is placed at the side of the column, at the lower part (Fig. 1). This sucks up the gas stored in the gasometer and the water contained in the reservoir, and forces them into the sphere. This latter is of bronze, cast in a single piece, and the thickness of its sides prevents all danger of explosion. It is silvered internally, and provided with a powerful rotary agitator that favors the admixture of the water and gas.
The apparatus it rendered complete by a bottling machine, which is placed either on a line with the apparatus or in front of it. This machine is connected directly with the sphere by a block-tin pipe.—Chronique Industrielle.
* * * * *
APPARATUS FOR MEASURING THE FORCE OF EXPLOSIVES.
Among the numerous apparatus that have been devised for determining the power of powder, those designed for military purposes are the ones most extensively used. Up to the present, very few experimental apparatus have been constructed for civil uses, although such are no less necessary than the others. Mr. D'O. Guttman has examined the principal types of dynamometers with respect to their use for testing explosive materials, and, after ascertaining wherein they are defective, has devised an apparatus in which the principle is the same as that employed by Messrs. Montluisant and Reffye at Meudon, that is to say, one in which the force of the powder is made to act upon a lead cylinder fixed in a conical channel. Mr. Desortiaux objects that in this system, when it is employed with charges for cannons, the action has already begun when only a portion of the powder is burned. To this, Mr. Guttman responds that his apparatus operates only with small charges (300 grains), which practically inflame simultaneously in every part when the igniting is done in a closed space. In order that the force may not be made to act in one direction only, the inventor uses two leaden cylinders. His apparatus is shown in the accompanying Figs. 1, 2, and 3. It consists of a median piece, a, and of two heads, b, of an external diameter of four inches. These pieces are of tempered Bessemer steel. The two heads are four inches in length, one inch of which is provided with a screw thread. Each of them contains an aperture, c, 1.34 inches wide below, 1.3 inches wide above, and 1.18 inches deep. This aperture is followed by another and conical one, d, 1.38 inches deep, and 0.4 inch wide at its narrowest end, and finally by another one, e, 0.4 inch wide, which runs to the exterior. The median piece, a, is 4 inches long. It is provided at the two sides with nuts, between which there is a cylindrical space, f, 1.8 inches long, designed to receive the charge. The inflaming plug, g, is screwed into the exact center of the median piece, a, which it enters to a depth of one inch. Into the space that still remains free is screwed a plug, h. The lower surface of the plug, g, contains a hollow space, 0.6 inch wide and deep. This hollow is prolonged by another one, 0.24 inch wide, and contains a valve, i, which has a play of about 0.08 inch. The three parts are connected by a key which passes into the holes, x, and are rendered tight by copper rings, y.
When it is desired to charge the apparatus, a leaden cylinder, 1.34 inches long and 1.3 inches in diameter, is placed in one of the heads, and the median piece is so screwed that it can be made still tighter by a few turns. Then a steel plate, k, 1.3 inches wide by 0.2 inch thick, is placed against the cylinder, and against this plate again is placed a cardboard disk, 1.34 inches wide by 0.4 inch thick. This completely closes the hollow space. The steel plates and heads are marked with the figures 1 and 2, which, through the pressure, are impressed upon the leaden cylinders. Then the charge of powder, weighing exactly 300 grains, is introduced, and a new cardboard disk, a steel plate, and a leaden cylinder are inserted, and the second head is screwed up. The apparatus is now ready to operate. An ordinary priming is placed on the pyramid, h, and the plug with the valve is screwed down in such a way that the latter shall have a little play. By means of a hammer, m, a smart blow is given the valve i, and this detonates the priming, and causes an explosion of the charge. The gases make their exit through the pyramid, h, and lift the valve and press it against the plug, so that their escape is effectually prevented. In fact, the explosion takes place without noise. A slight whistling, only, indicates that the capsule has not missed fire, and that the apparatus may be immediately opened, the gases having condensed in the interior. It is well, however, to place the closed apparatus in water, in order that the residua that have entered the threads of the screw may become detached, and that the apparatus may be opened easily. Although there is no danger in standing alongside the apparatus, it is much better to spring the hammer by means of a cord of a certain length, since the valve and especially the pyramid gradually burn and may be thrown out. With some kinds of powder the pyramid rapidly melts, and must be frequently replaced.
The two cones of lead obtained are then measured to 0.004 of an inch by means of a gauge (Fig. 3).
The inventor has made numerous experiments with his apparatus, and thinks it permits of determining the total force developed by powder very perfectly.
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SANDMANN'S VINEGAR APPARATUS.
For obtaining anhydrous or very concentrated vinegar directly from pyrolignite of lime or other acetates by a single distillation, Mr. D. Sandmann, of Charlottenburg, employs the apparatus shown in the accompanying engraving. It consists of a double-bottomed copper or enameled iron boiler, A, arranged for being heated by steam, and the upper part of which is protected against the action of the acid vapors disengaged during distillation by a lining of refractory clay. The stone cover, B, is provided with an aperture, b, through which the boiler is filled. The steam pipe, k, is inclosed in a second pipe, f, provided with radii. This tube serves as a stirrer; and is set in motion by means of a pulley, g. The tube, c, is connected with a worm, h, and the tube, d, which is provided with a valve, leads to the second boiler, C. The head, D, which acts, by reason of its internal arrangement, as a dephlegmator, is of enameled iron, and is provided with a thermometer, f, and an aperture, p. Above the spirals of the worm, e, are placed strips of glass, the free intervals between which are filled in with pieces of glass, porcelain, or any other material not attackable by acids. The arrangement is such that the rising vapors can regularly and without obstruction traverse these materials of wide surface. The condensed liquid falls back into the lower part of the boiler. The worm, e, debouches into a cooler, F, fed with water through the cock, n.
At the bottom of the boiler, A, there is fixed a tubulure, r, closed by a lever, s, and having a fastening device, o. This tubulure permits of emptying the boiler into the reservoir, L.
A like arrangement is found in the boiler, C. The valves, V, serve to introduce steam for heating into the double bottoms of the two boilers. The water of condensation flows out through the tubes, u. The water for cooling enters the coolers, F, J, and Z, through the cocks, n, and flows out through the tubes, v.
The acetate, previously crushed, is placed in the boiler, A, and the quantity of acid necessary to decompose it is added. The mass is afterward mixed with care by means of the stirrer, and the distillation may then proceed at once.
The vapors of acetic acid that are disengaged enter the boiler, C, through the tube, d, and are kept hot by the steam. In the head, D, they are separated into two portions, viz., into concentrated acetic acid, which condenses by reason of its high boiling point, and into steam, which distills and carries along but a very small amount of acetic acid. This steam passes through the pipe, G, into the worm, H, condenses, and afterward flows into the vessel, N.
The acetic acid that accumulates in the boiler, C, must be again vaporized and treated until it no longer gives off any steam at all through the pipe, G. The amount of cooling water admitted into the worm, e, that traverses the head, D, is regulated according to the degree of concentration it is desired to give the acid. As soon as the steam can no longer be separated in the boiler, C, and temperature has reached 118 degrees, the anhydrous acetic acid is distilled through the tube, g, and received in the cooler, K, wherein it condenses. When the contents of the boiler, A, have been distilled to dryness, the tube, d, is closed and the cock of the tube, c, is opened. After this, steam is injected directly through the tube, k, in order to distill the acetic acid that still remains in the residuum, and which passes thus through the tube, e, into the worm, h, and flows into the two-necked bottle, S.
There may be added to the boiler, C, certain materials for purifying the acetic acid, such as permanganate of potassa or acetate of soda, so as to obtain an absolutely pure article.—Dingler's Polytech. Journal.
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FIELD KITCHENS.
We illustrate the field kitchens of Captain J.C. Baxter, R.E., in the Inventions Exhibition. Figs. 1 to 3 represent Captain Baxter's Telescopic Kitchen, both open for use and packed up for traveling. These kitchens, which are on an entirely new principle, consist of from three to five annular kettles, either circular or elliptical, which are placed one on another, and the fire lighted inside the central tube. The kettles are built up on the top of the outer case in which they are carried, the central tube being placed over the grate in the lid. A small iron stand, supporting an ordinary pot, is placed on the top. When packed up, the annular kettles fit or nest into each other, and into the outer case; the iron stand packs inside the innermost kettle, and the top pot is placed on the outer case, being secured by a strap. This form of kitchen is intended for the use of officers, both regular and volunteer, and for officers' and sergeants' messes on active service or in camp. They are also suited for travelers, explorers, colonists, boating, shooting, and fishing parties, and in fact for all who may require to cook in the open air. Figs. 4 to 6 represent the kitchen of the field service pattern with conical kettles, while Figs. 7 and 8 represent the same pattern with elliptical kettles. These kitchens consist of five annular vessels, either circular or elliptical, which are placed one upon another, and the fire lighted in the central tube or flue. A small iron stand, supporting an ordinary pot or kettle, may be placed on the top as in the other set. A small hole, 18 inches long, 6 inches deep, and of the same width as the central tube of the annular kettles, may be made for an ashpit, or the kitchen may be raised a few inches from the ground on stones or turf. The annular vessels may be made cylindrical or conical; in the latter case they will fit or nest into one another, and save space when not in use. They may be made circular or elliptical. Those intended for cavalry are provided with straps to attach them to the saddle. This form of kitchen is intended for the use of troops on active service, or in camp or barracks, workhouses prisons, schools, and soup kitchens; also for cooking food for cattle and hounds; and for all who may require to cook and distribute quickly large quantities of food, soup, or tea, or to heat water rapidly at a small cost. The manufacturers are M. Adams & Son, London.—Iron.
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A NEW COP-WINDER.
In Germany extensive use is made of a cop-winding machine in which the wooden spindle consists of a cone moved by a screw, and the position of which is horizontal. Fig. 1 shows the primitive type of the German apparatus, in which the cone that forms the cop is set in motion by a horizontal screw. It is at first the greater diameter of the cone that moves the tube, and permits the thread to accumulate beneath the narrow extremity. But, as soon as a core of thread has been formed, it is in contact with the entire surface of the cone, and thus revolves with a mean velocity until it is finished.
In the new model (Fig. 2) the arrangement is different. Here A is the paper tube, with wooden base, to which it is freely attached, and C is the cone that moves over the screw, D. The thread passes into a groove which makes one revolution of the cone, and from thence over the paper tube, where it receives the form of a cop by reason of the transverse motion of the cone upon the screw. This transverse motion is at first prevented by the click, F, which falls into the teeth of the ratchet-wheel fixed behind the cone. The shaft revolves continuously, but has, at the same time, a to and fro motion in the direction of its axis, so as to cause the thread to move forward constantly and form a cop. This to and fro motion is obtained by means of a lever and a sleeve, I, the wheel, H, of the shaft being set in motion by the pinion, J, actuated by the transmission of the machine. As the spindle advances, a core is formed; the click, F, is then pushed backward, and the cone is kept in motion by the thread until the cop is finished.
Preference is usually given to the horizontal model; but the system may likewise be applied to a vertical spindle, and the arrangement in this case is simpler, as shown in Fig. 3. A rotary motion of the shaft is useless here, as the click, F, acts in an oblique position upon the ratchet-wheel, O, and pushes it by reason of the to and fro motion of the screw.
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[Continued from SUPPLEMENT, No. 513, page 8191.]
THE PRESERVATION OF TIMBER.
[Footnote: From the Transactions of the Society.]
REPORT OF THE COMMITTEE OF THE AMERICAN SOCIETY OF CIVIL ENGINEERS ON THE PRESERVATION OF TIMBER, PRESENTED AND ACCEPTED AT THE ANNUAL CONVENTION, JUNE 25, 1885.
BOUCHERIE, OR SULPHATE OF COPPER.
The name of Dr. Boucherie is generally applied to the process, which he invented and extensively applied, of preparing wood by forcing a solution longitudinally through the pores of the wood by means of hydraulic pressure. As, however, he also patented the use of sulphate of copper, and his name became attached to the use of that antiseptic, it will be convenient here to classify experiments made with that substance under this head.
Dr. Boucherie was a distinguished French chemist, who between 1836 and 1846 made many elaborate researches and experiments upon the preservation of timber. He tried many substances, and at first recommended the use of pyrolignite of iron, but subsequently used sulphate of copper, which he considered more effective.
His first experiments were conducted by vital suction, that is, by tapping the living tree, and allowing the ascending sap to carry up a preserving solution. This was not found to give uniform or satisfactory results, and Dr. Boucherie then invented the process which bears his name. This was practiced either by applying a cap to the end of a freshly cut log, through which the solution was allowed to flow by pressure, or by sawing a log nearly through in the middle, raising it at the center slightly, so as to open the joint, placing a strip of tarred rope or a rubber band just inside the periphery of the cut log, and letting it spring back, so as to form a tight joint by pressing upon the rope or band. An auger hole bored diagonally into the cavity so formed then served to admit the solution under pressure.
This process, applied with a solution of about one pound of sulphate of copper to one hundred pounds of water, has been extensively applied in France for many years, with satisfactory results. It was found, however, that to be successful it must be applied to freshly cut trees in the log only, and that this involved so much delay, moving about, waste, and annoyance, that it has now been abandoned. These difficulties would be still greater in this country, and in the Northern States the process could not be applied at all during the winter (or season for cutting down trees), as the solution would freeze.
On this page is a list of the experiments which your committee have been able to learn about, as having been made with sulphate of copper in this country.
RECORD OF AMERICAN EXPERIMENTS.
SULPHATE OF COPPER, OR BOUCHERIE.
+ + + + + + + - Material Subsequent No Locality Year Process. Treated. Exposure. Results. Authority. + + + + + + + - 1 Chili, S.A. 1857 Boucher. Poplar R.R. track Favorable W.W. Evans ties 2 Cleveland, O 1870 Thilmany Ties " " Favorable J.R. Conrad to 1875 3 Washington 1872 " Paving Laboratory Unfavor. W.C. Tilden blocks 4 Pensacola 1874 " Live oak Teredo Failure W.H. Varney 5 Charleston, SC 1875 " Pine block " " Q.A. Gillmore 6 San Francisco 1876 " " " " " C.S. Stewart 7 Milwaukee 1876 " " " Pavement Favorable, Schlitz Bg. 1882 Co. 8 Norfolk, Va. 1876 " Hackmatack Teredo Failure P.C. Asserson 9 Charlestown, 1877 " Various Laboratory Favorable J.F. Babcock Mass 10 Wabash R.R. 1877 " Ties R.R. track Unfavor. R.A. Houghton 11 Wabash R.R. 1878 " " " " " W.S. Lincoln 12 New York, 1879 " " " " " C. Latimer Pennsylvania, and Ohio R.R. 13 Lake Shore and 1879 " " " " " R.A. Houghton Michigan Southern R.R. 14 Cleveland and 1879 " " " " " C. Latimer Pittsburg R.R. 15 Charlestown, 1879 " Spruce Sidewalk Success S.G. White Mass plank to 1882 16 Baltimore and 1879 " Ties R.R. track Too recent J.L. Randolph Ohio 17 Hudson River 1869 Hamar " " " Success E.W. Vanderbilt R.R. 18 St. Louis 1882 Fladd " " " Too recent H. Fladd + + + + + + + - |
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