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16:59, 11 January 2016 (UTC)
Greatness A trivial matter... ”

“ The electric people laid down, from one office to another, a lead pipe some two inches in diameter, with an air-pump attached at the delivery end. The pipe passed downwards under the street, up again, and the open end curled over the office desk. A short cartridge-looking case with an opening at the side, to contain a roll of paper, being put into the pipe, and the pump set to work to exhaust in front of it, created sufficient vacuum to cause a rush of air and wind behind, and propel the cartridge like a bullet through a gun-barrel till it fell out on the desk where it was wanted. ”

“ If a non-automatic generator is decided upon, the hand carbide-feed or the flooded- compartment apparatus is almost equally good; and if automatism is desired, either a flooded-compartment machine or one of the most trustworthy types of carbide-feed apparatus may be taken. There are contact apparatus on the markets which appear never to have given trouble, and those are worthy of attention. Some builders advocate their own apparatus because the residue is solid and not a cream. ”

“ It is an almost dramatic moment when the machine is ready to start. The machine tender opens the valves which admit the stuff from the flow box and a stream spreads out onto the wire. At a given signal the back tender starts the wire, and the endless white stream moves smartly forward. Then ensues the mechanical imitation of making paper by hand, only instead of forming sheet by sheet, the formation is a continuous process in the web. The shake of the machine mixes the position of the fibers in the “pond” behind the slices ”

“ In a non-automatic apparatus the holder is nothing but a holder and may be placed wherever convenient, even at a distance from the generating plant; in an automatic apparatus the holder, or a small similarly constructed holder placed before the main storage vessel, has to act as a water-supply governor, as the releasing gear for certain carbide-food mechanism, or indeed as the motive power of such mechanism; and accordingly it must be close to the water or carbide store, and more or less intimately connected by means of levers, or the like, with the receptacle in which decomposition occurs. ”

“ The force which may, by a machine of this kind, be brought to bear upon substances submitted to its action, is limited only by the power of the materials of the press to resist the strains put upon them. If water be continually forced into the cylinder of such a machine, then, whatever may be the resistance offered to the ascent of the plunger, it must yield, or otherwise some part of the machine itself must yield, either by rupture of the hydraulic cylinder, or by the bursting of the connecting-pipe or the forcing-pump. ”

“ That simple appliance, a garden squirt, exemplifies two important kinds of apparatus, one the converse of the other. Fill the cylinder with water, force the piston along its course, and you have a pump. Admit water under pressure, as from a city faucet, and it drives the piston of a motor; in principle such is the mechanism of thousands of motors in London, using water under a pressure [372] of 500 pounds, or so, to the square inch. An apparatus, essentially the same, when supplied with steam or gas becomes the familiar engine at work in uncounted factories and mills. ”

“ The paper-making machine is supplied from the “chest” or reservoir (F) , into which the pulp descends from the beating engine, when sufficiently ground; being kept in constant motion, as it descends, by means of the agitator (G) , in order that it shall not settle. From this reservoir the pulp is again conveyed by a pipe [66] into what is technically termed the “lifter” (H) , which consists of a cast-iron wheel, enclosed in a wooden case, and having a number of buckets affixed to its circumference. ”

“ Apparatus which is supposed to be automatic should be made perfectly automatic, the water or the carbide-feed being locked automatically before the carbide store, the decomposing chamber, or the sludge-cock can be opened. The generating chamber must always be in communication with the atmosphere through a water-sealed vent-pipe, the seal of which, if necessary, the gas can blow at any time. All apparatus should be fitted with rising holders, the larger the better. ”

“ So many different types of carbureters have been devised, that it is difficult to select one which typifies all the best elements of construction.
[88]
In Fig. 31 we have shown a well known construction, and which will illustrate the features of the sprayer type to good advantage. The body of the device, represented by A, has a flange by means of which it is secured to the pipe which carries the carbureted air to the engine. The lower end of this tubular body is contracted, as shown at B, so as to form what is called a venturi tube. ”

“ The regulating-box, which has the effect of keeping a regular supply of pulp in the machine, is provided with two overflow pipes, which carry back to the stuff-chests any superfluous pulp that may have entered them, by which the stuff in the regulating-box is kept at a uniform level, while the machine is supplied with a regular and uniform quantity of the diluted pulp. The stuff-pump conveys the pulp through a valve in the bottom of the regulating-box in a greater quantity than is actually required, the superfluity returning to the stuff-chests by the overflow pipes ”

“ The pipe, d, connecting the two parts of the apparatus forks so as to lead the gas from one or the other of the generators, whence it passes into the copper washer within the base, then into the glass indicating washer, and then to the pump which forces it into the saturator.
Each of the generators communicates by special pipes, a, with a single safety vessel, V, that operates the same as in the preceding apparatus. The agitator, Q, is of bronze, and is curved as shown in Fig. 11. ”

“ Then the first receiver being, at the same time, emptied of its air, push the handle of the regulator, and the steam which rises from the boiler will act upon the surface of the water contained in the first receiver, where the force or pressure on it still increasing its elasticity, till it exceeds the weight of a column of water in another receiving-pipe, then it will necessarily drive up through the passage into the force-pipe, and eventually discharge itself at the top of the machinery. ”

“ A pump or exhauster to create a partial vacuum in the pipe line and so induce a high velocity air current in which the material will be conveyed. (2) An air filter in which any light dust carried over beyond the receiver is trapped, to prevent its entering the exhauster where it would quickly damage the piston rings and cylinder walls of reciprocating pumps. (3) A main receiver or discharger, and occasionally one or more subsidiary receivers, in which the conveyed material is extracted from the system and discharged into the receptacle or on to a dump as required. ”

“ The zinc and water are put into the generator first and corked down, and connections made with the iron or composite pipe to the purifier, which merely contains water (three parts full) , and a small quantity of lime—say, a piece the size of a walnut to a pint of water. Should there be any leakage round the pipe, stop it with loam or clay. Pour the acid into the generator, through the feed-pipe, with a funnel, in small quantities at a time. As the gas passes into the balloon you can [508] tell how quickly it is forming by the bubbling sound which is taking place in the purifier. ”

“ As the air pumps are set working a partial vacuum is formed within the tank, and as the nozzle end of the pipe is immersed into the grain to the depth of a few inches, the air and grain are drawn in at the mouth of the nozzle and carried along the pipe to the vacuum tank. The natural expansion of the air then lets the grain drop to the hopper bottom, whence it issues from an air-lock valve, while the air is drawn away by a pipe communicating with the pumps and is thence discharged into the open. ”

“ Machine batching is preferred by many firms because the application of oil and water, and the proportion of each, are much more uniform than they are by the above mentioned process of hand batching. On the other hand, there is no time for conditioning the fibre because the lubrication and the softening are proceeding simultaneously, although conditioning may proceed while the fibre remains in the cart after it has left the softener. ”

“ See that any workman repairing a generator first removes carbide and drains all water out, and disconnects it from piping and removes it to the open air, where he then fills all compartments with water to force out gas before using soldering irons. ”

“ The container is then forced by the pump against an elongated die of the size of the pipe required. A pressure from one to two tons per square inch is exerted, the lead is forced up through the die, and the pipe comes out completed. Wrought iron and cold steel can be forced like wax into different forms, and a rod of steel may be drawn through a die to form a piano wire.
By another modification of the hydraulic press pipes and cables are covered with a coating of lead to prevent deterioration from rust and other causes. ”

“ Water to Carbide Generators.--It is, of course, much easier to obtain a measured and regular flow of water than to obtain such a flow of any solid substance, especially when the solid substance is in the form of lumps, as is carbide This fact led to the use of a great many water-feed generators for all classes of work, and this type is still in common use for the small portable machines, such, for instance, as those used on motor cars for the lamps. ”

“ From this it will be seen that little or no harm can possibly occur either to the fibre or the metal work of the machine by the employment of the neutralising agents named, and when it is borne in mind that the simple washing of the pulp would occupy the beating-engine for a lengthened period and exhaust a considerable quantity of water—which, as we have said, would in some mills be a serious matter—the adoption of the neutralising method would undoubtedly have the preference. ”

“ But when the pump forces fresh mixture into one end, J, of the heating tubes, D, D, D, D, the exit-valve, I, is thereby forced open to allow an equal amount of the mixture, which has been operated upon, to escape out of the cooling tubes, H, H, at the other end of the apparatus. No steam or air should be allowed to accumulate in the tubes, which should be kept entirely full of the mixture. ”

“ Before we deal with the cylindrical machine we must, however, devote a few words to the electrophorus by which the jar can be charged if desired. An electrophorus is easily made. Choose the lid of a tin canister about eight inches in diameter and half an inch deep for your ‘form,’ or have a lid specially made by a tinsmith with its sharp edge turned over a wire ring, so that it may keep its shape and not be so likely to cut your fingers. Let the tinsmith also make you a thin flat disc of zinc or brass, smooth and rounded at the edges, and measuring about six inches and a half across. ”

“ The refiner is best employed to clear or brush out the mass of pulp after a certain amount of preliminary treatment in the beater, as the refiner cannot produce the effects obtained by actual beating as in the Hollander.
Fig. 53.—A “Tower” Beating Engine with Centrifugal Pump for Circulating Pulp.
Power Consumption.—The long treatment required to thoroughly pulp a strong material demands a great amount of power. Engines differ considerably in their power consumption, and comparisons are frequently made in terms of the power required to beat a given weight of pulp. ”

“ The empty carrier then passes through a little door at the side of the building, and drops into the yawning mouth of an automatic tube. In the twinkling of an eye it appears in front of the operator in one of the distributing stations, where it is refilled and returned to its proper loading machine, in order to keep the machine going at a perfectly uniform rate; while at the same time it allows but a minimum amount of powder to remain in the building at any moment. Each machine has but just sufficient powder in its hopper to run until a new supply can reach it. ”

“ The stock is then hosed and pumped into a washing-tank, where it acquires the proper consistency for the machine. From here it is pumped into the stuff chest, whence it goes over a set of screens and on to the machine, from which the finished fibre is run off on spindles. The rolls are made of a convenient size to handle, averaging about 100 lbs. each. The fibre is dried on the machine by passing over a series of iron cylinders heated by steam. ”

“ The mechanism of an electric pipe locator is not at all complicated, consisting only of an induction coil with battery, and a telephone receiver connected to a coil of a large number of turns of thin copper wire. ”

“ Leaning over, I discovered a small cylindrical jar, having the capacity of about a quart, which was suspended at one side of the driving shaft. The straps that held it in place allowed it to swing in any direction with the movement of the machine, but any sudden jar was impossible.
“Is it like nitro-glycerine?” I asked, eyeing the cylinder with an involuntary shudder.
190 “Not at all,” replied the inventor, calmly closing the trap again. “It is a much more powerful explosive, in its concentrated form, but may be diluted to any strength desired. ”