Read Ebook: Scientific American Supplement No. 299 September 24 1881 by Various
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Steam Ferry Boats of the Port of Marseilles.--2 figures.-- Transverse and longitudinal sections
Opening of a New English Dock. 1 figure
Improved Grain Elevator. 1 figure
Improved Dredger. 1 figure.--Single bucket dipper dredger
Railway Alarm Whistle
Furnace for the Manufacture of Sulphide of Carbon. 1 figure
Brouardel's Dry Inscribing Manometer. 1 figure.--Gas indication of manometer
Centrifugal Apparatus for Casting Metals. 4 figures.--Centrifugal metal moulding apparatus
Apparatus for the Manufacture of Wood Pulp. 2 figures.--Dresel's wood pulp apparatus
Recent Progress of Industrial Science.--Presidential address, Convention of Mechanical Engineers
The Hoboken Drainage Problem
The Removal of Noxious Vapors from Roasting Furnace Gases
New Gas Exhauster. 1 figure
Advance in the Price of Glycerine
Analysis of Oils or Mixtures of Oils Used for Lubricating Purposes
Nitrate of Amyl
Lightning and Telephone Wires
Conditions of Flames Under the Influence of Electricity
The Electric Stop-Motion in the Cotton Mill
Method in Madness
Hot Water Compresses in Tetanus and Trismus
Trials of String Sheaf Binders at Derby, England
The Culture of Strawberries.--Garden culture.--Field culture
Some Hardy Flowers for Midsummer
The Time Consuming Match
Artists' Homes. No. l4.--Bent's Brook, Holmwood, Surrey, Eng.-- 6 figures.--Perspective, elevations, and plans
ACHILLE DELESSE.
It is not only upon subjects relating to the history of rocks that Delesse has touched. Witness his work on the infiltration of water, as well as his volume relating to the materials of construction, published on the occasion of the Exhibition of 1855. The nature of the deposits which operate continually at the bottom of the sea offers points of interest which well repay the labor of the geologist. He finds there, indeed, a precious field to be compared with stratified deposits; for in spite of the enormous depth to which they form a part of continents, they are of analogous origin. Delesse laboriously studied the products of the innumerable soundings taken in most of the seas. He arranged the results in a work which has become classical with the beautiful atlas of submarine drawings which accompany it. Though he never slackened in his own especial work, he made much of the work of others. The "Revue des Progr?s de la G?ologie," with which he enriched the "Annales des Mines" for twenty years, would have been sufficient to engross the time of a less active scientific man, and one less ready to grasp the opening of a discovery. This indefatigable theorist never neglected the applications of science: the nature and the changes of the layers which form the under earth; the course and the depth of the subterraneous sheets of water; the mineralogical composition of the earth's vegetation, were represented by him on several charts and plans drawn out in proper form. His maps which follow the route of many of the great French lines of railway explain the kind of soil upon which they are laid, and are of daily use. In the pursuit of his numerous scientific works, Delesse never failed in discharging his duties in the Corps des Mines. Having in 1864 quitted the service of the Government of Paris, which he had occupied for eighteen years, he was made professor of agriculture, of drainage, and irrigation, at the School of Mines, where he established instruction in these before being called to found the course of geology at the Agricultural Institution. Promoted to be Inspector-General of Mines in 1878, and charged with the division of the south east of France, he preserved to the end of his life these new duties, for which, to the regret of the School of Mines, he gave up his excellent lessons there. During the year of 1870 Delesse fulfilled his duties as a citizen, as engineer in preparation of cartridges in the department.
THE ELECTRIC LIGHT AT EARNOCK COLLIERY.
LIGHTNING AND TELEPHONE WIRES.
Such lightning conductors usually consist of a toothed plate attached to one wire, close to another plate not toothed attached to the other wire. The copper even of such a conductor has been melted by the powerful current which it has carried away. In telephonic central offices, M. Bede has seen all the signals of one row of telephone wires fall at the same moment, proving that an electric discharge had fallen upon the wires, and been by them conveyed to earth.
This fact shows that wires, even without points, are capable of attracting the atmospheric electricity; but it must be remembered that there are two points at every join in the wire. M. Bede insists strongly upon the uselessness of terminating lightning conductors in wells, or even larger pieces of water. The experiments of MM. Becquerel and Pouillet proved that the resistance of water to the passage of electricity is one thousand million times greater than that of iron; consequently, if the current conveyed by a wire one square mm. thick were to be carried off by water without increased resistance, a surface of contact between the wire and the water of not less than 1,000 square meters must be established.
It is obvious that a wire let down into a well is simply useless. On the two-fluid theory, it offers no effectual way of escape to the terrestrial electricity; according to the older views, it would be absolutely dangerous, by attracting more electricity from the clouds than it could dispose of. The author advocates connecting lightning conductors with water or gas pipes, which have an immense surface of contact with the earth.
CONDITION OF FLAMES UNDER THE INFLUENCE OF ELECTRICITY.
The experiments of the author have been principally directed to the alterations in shape and color produced in a flame when under the influence of positive or negative electricity. The flames were arranged so as to form one electrode of a frictional machine. When charged with positive electricity the flame became more blue, narrower, and pointed at the top, while little or nothing of the result was observed in negative flames.
A peculiar result is that the end of a negative flame returns to its own conductor, and that, according to the intensity of the electricity, and also depending on the width of the burner, this turning back of the flame is either intermittent or constant. Most noticeable are these results:
When the flame rises from a circular burner, or when burning round a metallic cylinder, in the latter case it returns to the metallic surface according to the intensity of electricity in an arc or angle, while the point of the flame divides into two branches, which separately perform more or less equal movements. If a body connected to the earth by a conducting wire is held opposite the flame at some distance, the flame will in all cases bend toward it; as the body is brought closer, the flame, if negative, will be repulsed, and, if positive, will be attracted, at least the upper luminous part of the flame, while the lower dark body of flame is also repulsed.
This phenomenon explains why a positive flame will burn through wire gauze, while a negative flame remains below the gauze. The positive flame becoming pointed explains the fact that this will drive a small fan wheel, while a negative flame will only just move it.
All these results are most prominently obtained with a pure gas flame, a stearine, wax, or tallow candle, very indifferently with a spirit flame, and least from a Bunsen flame rich in oxygen. They may not only be obtained with flames electrified direct, but also when placed under the influence of a long "Holtz" machine.
A flame placed between two small disks on the machine bends toward the negative pole, becomes widened, and, at a certain point of electric intensity, commences to vibrate and oscillate, exhibiting a peculiar stratification. Since these phenomena are also least observed in flames rich in oxygen, it appears to be a general law that carbon and hydrogen are more strongly attracted by the negative pole, while oxygen is more attracted by the positive pole, probably like in all polar differentially attractions, in consequence of a peculiar unipolar conductivity of the substances.
THE ELECTRIC STOP-MOTION IN THE COTTON MILL.
The number of inventions for use as stop-motions in and about the various machines in the cotton mill has been to a certain extent something like the search after perpetual motion. Very available and quite satisfactory stop-motions have for a number of years been employed wherever the thread or sliver has been twisted so that strength was given it to resist a slight amount of friction, but the main trouble in the mill has been done after the sliver leaves the railway head and during its transit in the various processes employed between the railway head and the spinning frame or mule. Every carder or spinner knows that where an injury comes to the sliver because the sliver is soft, but partially condensed and very susceptible to injury, the injury is magnified and multiplied in every successive process. Virtually the field was long since abandoned for an accurate quick-working motion that should be applicable to any and all the machines and to every sliver or strand of the machine.
This invention was solved practically about two years since, and is now being employed as applied to drawing frames, doublers, speeder, intermediate, and slubber. It is a very cunning mechanical appliance, too, and has found favor to a great extent in England, where several thousand heads of drawing and speeders are already supplied.
This invention was exhibited at the Centennial in 1876, although in a somewhat crude state. Since that time it has been materially improved, and mechanically is very nearly perfect now. Many attempts have been made to apply a stop motion, which should be quick in its movement and accurate in its result, to carding engines or the card, not one of which, until the application of electricity, was worth the time spent in putting it on. With the electric motion, however, all this is changed, and the electric attachments are not of necessity so fragile as to be un-mechanical or to be not practical. The advantage has also been taken, in a mechanical way, of using cotton as one element, and, being non-conducting, so that no trouble shall arise from contact with the working parts of the electrical apparatus with the cotton itself.
To take into consideration all the possibilities that exist from the railway can to the front of the fine speeder is not needed by the practical reader, and would be useless to any other. The principle of this invention is the supplying of a magneto-electric current from a small magneto-electric machine attached to the card, speeder, or whatever machine it may be applied to which generates the current, and this machine is driven by a small belt from the main driving shaft. The machine in itself weighs but a few pounds, and can be driven by a half-inch or three quarter-inch belt, and requires a little more power than a light-running sewing machine.
One pole of the magneto-electric machine is connected by means of a rod or wire to the machine frame upon which it is to be used, and the other pole to the electromagnet in the ordinary way of conductivity of current, which means stretching the wire from one to the other. An armature is arranged so that when a thread is broken or a sliver or a strand of roving, the armature drops into a ratchet wheel; this ratchet wheel is made to revolve by the belt, and whenever it is impeded or stopped in its course it acts upon mechanism which throws the driving belt of the machine upon the loose pulley. Electrical contact is made by a very simple contrivance, and these attachments are only to act in the case of a breakage of a thread or strand.
As applied to a card, the calender rolls are both connected, one with the negative and one with the positive pole; when the sliver of cotton is between the calender rolls there is no connection, but if the sheet breaks down between the cone and the calender roll, the moment the calender rolls come in contact the electrical attachment operates and a stoppage ensues; and in the case, as with the American system, where a number of cards are used in a railway, this electric contact may be used for either one of two purposes-to stop the feeding of cotton into the card, or to ring a bell sharply and continue ringing it until the sliver is put between the calender rolls again and the card set to delivering cotton.
In drawing frames it may be attached so that, in the case of a breakage between the front roll and the calender roll, the electric machine acts; in the case of a lap upon one of the rolls or one end of the roll, or in case of breakage of the sliver at the back of the machine, in either case a stoppage would be instantly produced.
In being applied to the slubber a breakage either at the front or back can be arranged for. Upon intermediates the breakage of either one of the strands, if the machine was running two into one, from the creel to the roller, would cause the stoppage of the machine, or the breaking or tangling of ends between the front roll and the nose of the flier.
ON THE PROGRESS AND DEVELOPMENT OF THE MARINE ENGINE.
The author began by referring to a paper read at the Liverpool meeting in 1872, by Mr. F. J. Bramwell, F.R.S., on "The Progress effected in Economy of Fuel in Steam Navigation, considered in Relation to Compound Cylinder Engines and High-pressure Steam;" then proceeded to continue the subject from the date of that meeting, to trace out whether any, and if so what, progress had been made; further, to consider whether or no we have reached the finality so strongly deprecated by Sir Frederick Bramwell in the discussion referred to, and, if not, then in what direction we are to look for further development.
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