Title of the piece: | The World's Work |
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Author: | staff of Scribner's Monthly magazine |
First published: | Scribner's Monthly magazine; February, 1876 |
Copyright: | Public domain |
THE most recent contribution to the solar heat problem presents some features that are both interesting and promising. The apparatus consists of a cone-shaped reflector of polished brass, or silvered sheet metal, mounted on an iron frame, with suitable machinery for keeping it adjusted to the movements of the sun. The cone opens, or flares, at an angle of 45 degrees, and may be made of any convenient size. Supported in the center of this inverted cone is a copper boiler for generating steam. This is made in two parts, and, being hollow in the center, holds the water in a thin annular sheet next the outside. At the bottom is a pipe for supplying the water, and at the top a pipe with proper safety valves, etc., for the steam. The exterior of the boiler is blackened to assist in absorbing the heat, and over it is placed a bell glass to prevent the access of cooling currents of air. On supplying the boiler with water and exposing the apparatus to the full sun, steam was raised, and kept at a high pressure without difficulty. The first apparatus of this kind used a reflector having a base, or opening, 2.60 meters in diameter, while the boiler held 20 liters of water. On a clear day in May steam was raised to a pressure of two atmospheres in forty minutes, and soon rose to five atmospheres. In July the apparatus raised 15 liters of water to steam an hour, and the steam was made available in driving a small steam-engine. The apparatus has attracted much attention, and is still under experiment.
THIS new fabric consists of sheets of cork and cloth united by a preparation of India-rubber, and, in the form of blankets, tarpaulins, horse and carriage covers, clothing, buckets, tent material, etc., has attracted much attention. Its manufacture is simple and inexpensive. Thin sheets of cork are given two coats of a solution of crude rubber on one side. Canvas, linen, or other material is then treated in the same way. When cold, the sheets of cork are laid closely on the canvas and pressed down firm. Two more coats of rubber solution are then given to the other side of the cork, and more of the linen, or other fabric, similarly treated, is laid over it. The three sheets are submitted, when cold, to heavy pressure, and the new material is finished. It then consists of a layer of cork inclosed between two pieces of cloth and united by films of rubber, and is said to be both water-proof, flexible, strong, and a good resistant to heat and cold.
TO reduce the temperature in a factory in Paris, recourse was had to an inexpensive form of air cooler. A thin plate of metal, perforated with holes one-tenth of an inch in diameter, and having a total area equal to one-ninth of the surface of the plate, was set at a slight angle in a tight box. Over this plate a thin sheet of water at a temperature of 55 Fahr. was allowed to flow steadily, and by means of a power-blower air was forced into the box below the plate. By its pressure the air forced its way through the holes in the plate and through the water, and was then led by pipes to all parts of the factory. By this device, the air in the room was reduced to 57 Fahr., or within four degrees of the temperature of the water. Other experiments gave varying results according to the initial temperature of the water, but in each case the apparatus reduced the temperature of the current of air to within seven degrees of that of the water. Steam power is required for the blower, and, for the best results, the supply of water must be abundant and its temperature low. The application of this device might, in our warm climate, prove of use in pork-packing and other industries where a low temperature is desirable.
THESE two instruments are designed for measuring plain surfaces, fabrics, etc., and for measuring distances on scale maps. The machine for measuring surfaces, cloths, etc., is somewhat larger than a watch, has three sets of figures, three hands, and a slight projection on one edge in which plays a small wheel. The figures on the face are arranged in three rings. The outer circle represents ten inches and fractions of inches. The next ring gives feet, from one up to ten, and the smaller circle of figures corresponding to the second figures of a watch, give ten feet each, up to a hundred. The long hand points to the inches, the short hand to feet, and the little hand to the groups of ten feet. To use the instrument, set the hands at 1, or zero, and then, holding the instrument upright in the hand, let it run on its wheel over the surface to be measured. It will then record on its face any distance up to 100 feet, and without examination or error, and without reference to the path followed by the wheel. It may follow curves, corners, or any other trace, however complicated, and if a number of pieces of cloth are to be measured, will give the total result without regard to the stoppages or changes from one piece of goods to another. To measure greater lengths than 100 feet, it is only needed to notice how many times that point is passed. The other instrument, called a charto-meter, is smaller, and has only one hand, and one set of figures on its face. It is designed for measuring distances on maps drawn to a fixed scale. Its wheel will follow any path, however crooked, and it will give the total distance in miles according to the scale of that particular map. For maps of other scales, different dials are supplied, and may be easily inserted in the charto-meter. For maps of unusual scale, as 22 miles to an inch, a dial is used giving 11 miles to an inch, and the result is multiplied by 2. For a map drawn to 3 miles to an inch, a dial graded to 6 miles is used, and the final result divided by 2 gives the distance in miles. For persons using coast survey charts and other important maps, and for persons measuring great quantities of stuffs, papers, etc., these two instruments seem likely to prove useful.
THIS novel and interesting machine consists of a hollow metallic pen-handle of the usual length, and inclosing a slender needle. The end of the pen-handle is drawn to a point ending in a minute hole. Inside the pen is hung a slender wire, having a common cambric needle soldered to the end. At the top of the pen-handle is a small electro-magnetic machine, provided with a circuit breaker of the usual form and an eccentric wheel, whereby the circular motion of the machine is transferred to an up and down stroke. The interior wire, bearing the needle, is secured to this, and performs an up and down motion, thrusting its point through the hole in the end of the pen-handle at every stroke. Flexible wires connect the electro-magnet with a two-cup battery, and, when prepared for work, this is sufficient to give the needle about 1,000 strokes a minute. By holding the pen upright over a piece of writing-paper, any writing, drawing, plan, tracing, or print may be made on the paper as quickly as the operator can move his hand. So far there is no ink used, and when the letter or drawing is finished, there is nothing visible except the lines of minute holes punched in the paper. Hold the paper up to the light, and the writing or drawing is plainly seen. By laying the sheet on other paper and holding it firm, it may be inked with a printer's hand-roller, and it thus becomes a stencil-plate. The ink readily passes through the holes made by the needle, and many hundred copies may be thus taken. A single copy can be made in less than half a minute, and if the paper stencil becomes worn or is destroyed, another is quickly and easily made. This pen has already proved useful in copying letters, plans, music, and drawings of all kinds, and new uses in the dress-making and embroidery trades are now being developed.
THIS new propeller, designed for occasional use on sailing ships, was first shown at the recent Maritime Exhibition, Paris. As sailing vessels in our coastwise marine now frequently carry a small steam-engine for handling the sails and cargo, the idea of employing a propeller to be used in calms, against head-winds, or as occasion demands, would seem available were it not for the fact that a fixed propeller would only be a drag when not in use. This apparatus is designed to overcome this objection. It consists of an iron frame hung on hinged arms at the stern, and bearing in the center an upright shaft. At the lower end of the frame-work are two toothed wheels for transmitting the motion of the shaft to a short propeller shaft hung below. At the top of the upright shaft is a horizontal grooved wheel for a belt that extends inboard to a wheel connected with the engine. When ready for work, the apparatus hangs partially submerged just behind the rudder, and, by the means of the belt, the propeller is readily turned and the vessel moved. When the ship is under sail the belt is thrown off, and by the aid of a hand-windlass on the deck, the whole apparatus is lifted out of the water, and may be secured to the edge of the rail, just where the ship's boat commonly hangs. The apparatus may be lowered and put in order in less than five minutes, and in escaping calms, navigating crooked rivers and canals, and against light head-winds, will, in the opinion of marine experts who have examined it, prove of great value.
THE accidental discovery of the artificial incubation of ostrich eggs some years since in Algeria has, after many disappointing failures, led to practical commercial results. From Algeria the idea of domesticating and raising ostriches for their feathers, in time spread to the Cape of Good Hope, where the business has now assumed the position of a great and growing interest. The chicks are almost wholly raised by artificial means, and during their entire life are supplied with food and shelter like so many domestic fowls. The birds grow up comparatively tame, though they never seem to lose a certain irritableness of temper. The ostrich farms are usually very large, and to start and maintain one demands at least $10,000 capital. The business has also extended to South America, and is reported to be profitable. The chicks give salable feathers during the first year, and increase in productiveness up to five years of age, when they mature. The birds are said to be hardy and healthy under the semi-confinement of the farms. The business has been suggested as available in our Gulf States.
A NEWLY patented method of keeping hops employs carbonic acid as a preservative agent. Airtight, tin-lined boxes are loosely filled with hops. Carbonic acid (made in a soda fountain machine by the usual sulphuric acid and marble dust process) is then admitted to the box through a tube that reaches to the bottom. The gas fills the box, driving the air out before it as it rises from the bottom. The hops are then compressed, and more filled in with an additional supply of gas. This is repeated till the box is loaded with pressed hops saturated with carbonic acid. The cover is put on, and more gas is added under pressure to drive out the last trace of air, and then the box is quickly sealed hermetically. The first experiments in this direction proved entirely successful.
ONE of the most interesting applications of centrifugal force is shown in a new speed indicator. The apparatus consists of four glass tubes placed upright in a brass framework that turns horizontally. One tube is placed in the center and in front of a brass plate (like a thermometer), on which are marked the figures that represent the speed. The other tubes stand at equal distances outside the central tube. All are joined together by cross pipes at the bottom, and the top of each is left open. Mercury is poured into one and finds its level in all, and rising in the center tube to any desired point on the scale. By means of a small belt the apparatus is connected with the engine, press, or other machine, and turns horizontally with it, fast or slow, as may be. The revolution of the three tubes round the central one causes the quicksilver to rise by centrifugal force in each, at the same time dragging down the column in the central tube that is merely turning on its own axis. The top of this column of mercury then indicates the speed at which the machinery is moving, and the slightest variation of the speed is shown visibly. The rapid movement of the three outside tubes past the scale does not interfere with the sight in reading the instrument.
IN removing soft mud and silt from sea and river bottoms, a notably interesting device has recently been exhibited. The plan is to use a steam-tug or barge of large size and fitted with powerful engines, both for its propulsion and the movement of its dredging machinery. Just abaft the center of the boat, four holes are made in the bottom, and to these are fitted iron pipes, having flexible joints, so as to hang freely below the keel. These are joined together by a frame-work, and, by means of a crane at the stern, they may be raised or lowered at will. Each pipe terminates in a bent shoe, having openings at the sides. When at work, they rest lightly in the mud at the bottom, and, being flexible, readily adjust themselves to the changing depth caused by the waves, the tide, or the shoaling of the water. Through these pipes is sucked up, by the natural pressure caused by the displacement of the boat, the loose mud and sand to be removed. It enters the hold of the boat under considerable pressure, and, by the aid of steam-pumps, is thrown up through pipes to the deck, and thence outboard into barges alongside. Fitted with such tubes, each 10 inches in diameter, such a boat, it is estimated, will lift and discharge 32,000 yards of silt in 10 hours. With clean sand, an increase of 20 per cent over this is estimated. The plan also presents another interesting feature in a machine for tearing up and loosening hard packed silt, and preparing it for the suction tubes. This consists of an iron fork or harrow, revolving on its own axis, and supported on a framework, lowered by chains from the bow. By this means it is kept at any required angle, and, by means of a chain belt, it is caused to revolve, and thus tear and rip up the bottom just in advance of the pipes. When at work, the boat is designed to be advanced, by means of a line secured to moorings, and leaving a path on the bottom of varying depth, according to the character of the material. Each pipe sucks up a wide area about its mouth, and, in case of choking or stoppage, may be instantly cleared by raising the pipes from the bottom and allowing the clear water to sweep through. When not in use, the harrow and the pipes may be raised to the keel, and the boat then moved to another spot. This new dredging machine has been made the subject of exhaustive experiment, with satisfactory results.
THESE chemical lights are now made in a variety of forms, and serve a useful purpose in giving a bright light upon the water when thrown overboard. One of the best of these contains chemicals that will not burn at any application of heat, but touched by water will evolve a bright flame. A small cylindrical box, ending above in a soft copper nib, is weighted below to keep it upright in the water, and filled with phosphate of calcium. When thrown into the sea, after the copper nib has been cut off, the water penetrates into the box, and the phosphureted hydrogen evolved escapes through a perforated tube leading to the open nib in a brilliant jet of light. Rain and spray only increase its brilliancy.
IN the manufacture of bricquetts, or brick of coal-dust, for fuel, a slight modification of the usual Belgium process is announced. Instead of using water in making the coal-dust into a paste, a boiling mixture of tar and pitch is employed. To this is added sulphate of lime to remove the ammonia of the tar. The mixture is composed of 33 1/2 parts of pitch, 13.6 of tar, and 1.80 of sulphate of lime, to one ton of coal-dust. The experiments going on in this department of fuel economy in this country have reached a practical stage in Pennsylvania, and fuel manufactured from coal-slack is already being extensively employed. So far, the reports are favorable to the quality of these American bricquetts, and they are being freely introduced on locomotive engines. A French company is now extensively manufacturing kindling material for domestic fires by utilizing corn-cobs. Two processes are employed. By one, the corn-cobs are first steeped in hot water containing 2 per cent. of saltpeter, and then saturated with resinous matter. By the other process, the cobs are soaked in a hot mixture of 60 parts resin and 40 parts tar. They are then dried, and afterward baked on a plate heated to 212 Fahr. Assorted and secured in bundles, they sell at the rate of four for an English halfpenny, or, at wholesale, for $2 or $3 a thousand. A process for utilizing corn-cobs by saturating them with resin has been patented in this country, and their manufacture has been attempted. The inventor already reports an active demand for them as domestic fire-lighters.
FROM the official reports concerning the hood placed over and before the screw of the British warship Bruiser, and from recent experiments with a new propeller for canal boats, some interesting facts are added to the science of sea and inland navigation. The hood or casing of iron plates placed about the screw of the steamship Bruiser resulted in increased speed, and less jar or motion to the ship. It also prevented, in an appreciative degree, the racing of the engine when the screw ran out of water in a high sea, by holding a certain amount of water about the propeller. The hood also serves as an effectual guard in preventing floating debris from fouling the screw. The new canal boat propeller consists of a large sheet-iron screw or wheel, 7 feet in diameter, hung in the air at the stern, and just clear of the water. A canal boat 40 feet long and drawing 13 inches was driven at a speed of four miles an hour with this screw, making 400 revolutions a minute. The power employed was a common upright engine with an eight-inch cylinder. The practical results obtained with this air-wheel were sufficient to warrant the inventors in constructing another, which is soon to be tried on the Erie Canal.