Page:Encyclopædia Britannica, Ninth Edition, v. 9.djvu/427

FOR- by a powerful air blast situated at one end of the building. The air is conveyed by a series of main pipes sunk to the depth of a few feet under the ground. Smaller tubes are employed to convey the blast to the hearths. Under these circumstances the smith has but to turn a small lever, in order to open or close the air-valve which is placed in a small standard at the side of each hearth. By this means the workman is saved much labour and consequently much time. Steam has also been adopted as a means of forcing air into the forge. With special apparatus for drying the 6team it is very successful. It is, however, more adapted to large blast furnaces than those of the smithy. Another description of the forge is the battery forge. This is used in military service. It is constructed somewhat like a caisson. The bellows are situated in the place usually occupied by the ammunition chests. A box to contain coal, a set of tools, horse shoes, iron, and steel is attached to the body of the carriage, which is mounted on a pair of wheels. The forge gives its name to "Forging," one of the most important arts connected with engineering work. The strength and durability of engines and other machinery in general depends to a very great extent upon the art and care bestowed upon those parts which have to sustain great weight, much strain, and an amount of wear and tear. Thus the smith holds in engineering shops a very important place. He has to depend upon his eye and judgment in many cases where the fitter and turner is assisted by drawings setting forth every detail. The smith, however, of the present day is not such an adept as his predecessor. The introduction of the steam hammer, stamps, tfec., have to a great extent rendered his work nothing more than mechanical. To meet the urgent re quirements of the present day, he has to study the engine and machine ; that he has succeeded is evident, and the manufacturer can produce more work in less time than he could formerly. But though this is undoubtedly a gain, it has unfortunately been the means of rendering skilled manual labour in many branches of our industries almost superfluous. This being the case, the skill on which the older workmen so much prided themselves is slowly disappearing, and indeed has become almost extinct. One great change in the history of forging was the introduction of the steam hammer in 1833 by Mr Nasmyth. By the means of that machine, the welding and forging of pieces of metal of any size has become comparatively easy. Mr Nasmyth s steam hammer has been improved upon by himself from that time, and is now to be seen in almost all engineering shops throughout the world. The tilt hammer is still in use, and for various purposes may be said to be of great utility. But the smaller sizes of steam hammer are more convenient and manageable, and as a natural consequence are rapidly taking its place. To the steam hammer we are indebted for the Y anvil, which is used in the forging of rods and bar iron. Rolling mills are, however, much quicker, and are used in preference. A forging machine, invented by Mr Ryder many years back, and still in full operation, possesses many qualities unattainable by any other known means. It consists of a series of small anvils of various sizes. These are held by set screws passing through the frame of the machine, which allow of the anvils being raised or lowered, so that a perfect adjustment might be obtained. The hammers are placed over the anvils, and work up and down in bearings, moved by an eccentric. This is worked by a cradle upon the head ; the hammer is raised by a strong spiral spring. The strokes made by this machine vary from 600 to 1200 per minute. According to Mr Platt (of Platt Brothers, Oldham), one of the original makers of the machine, it is rather a squeeze than a blow which does the work. Many improvements hava been added to it by Mr F R 413 Platt s firm ; and the Bolton blacksmith, as it is commonly called, is now being extensively used in the Government workshops for the manufacture of bayonets, <fcc. The tools used are wedge-shaped, and the surface of the iron after forging, or rather squeezing, is said to be anything but hard or difficult to file up. The spindles of mules (cotton- spinning machines) are now forged by this tool, and indeed every description of small work. The contour produced by it is such that the work is almost as true as though it had been surfaced in the lathe. There have been several other machines upon Ryder s principle brought out, but none appear to answer so well as that designed by the original inventor. Another invention, the steam stamp, is now most ex tensively used. This is similar to a steam hammer ; in place of the anvil and hammer head is placed a pair of dies, in which is cut the form of work necessary. The iron is placed over the die, the stroke is delivered, and the iron is forced into the shape of the die. Machinery and separate tools are now often forged in this hammer. The quality of the coals used in forging is of the utmost importance; the coal preferred by smiths is that which makes plenty of coke, and which leaves after being burnt a quantity of white ashes. The art of forging is by no means easy to acquire. Great practice is necessary to arrive at excellence in this important branch of our great industries. See The, Forge (published by the Society for Promoting Christian Knowledge), W. Harrison s Light of the Forge, and The Smith s and Metal Worker s Director, (D. A. A.) FORGERY, in English law, is defined as " the fraudu lent making or alteration of a writing to the prejudice of another man s right," or " as the false making, or making malo animo, of any written instrument for the purpose of fraud or deceit." This definition, it will be seen, com prehends all fraudulent tampering with documents, " Not only the fabrication and false making of the whole of a written instrument, but a fraudulent insertion, alteration, or erasure, even of a letter, in any material part of a true instrument whereby a new operation is given to it, will amount to forgery, and this though it be afterwards executed by another person ignorant of the deceit " (Russell on Crimes and Misdemeanours, vol. ii. p. 619). Changing the word Dale into Sale in a lease, so that it appears to be a lease of the manor of Sale instead of the manor of Dale, is a forgery. And when a country banker s note was made payable at the house of a banker in London who failed, it was held to be forgery to alter the name of such London banker to that of another London banker with whom the country banker had subsequently made his notes payable. As to the fraud, " an intent to defraud is pre sumed to exist if it appears that at the time when the false document was made there was in existence a specific person, ascertained or unascertained, capable of being defrauded thereby ; and this presumption is not rebutted by proof that the offender took or intended to take measures to prevent such person from being defrauded in fact, nor by the fact that he had or thought he had a right to the thing to be obtained by the false document " (Stephen s Digest of the Criminal Law, c. 43). Thus when a man makes a false acceptance to a bill of exchange, and circulates it, intending to take it up and actually taking it up before it is presented for payment, he is guilty of forgery. Even if it be proved as a matter of fact that no person could be defrauded (as when A forges a cheque in B s name on a bank from which B had withdrawn his account), the intent to defraud will be presumed. But it would appear that if A knew that B had withdrawn his account, the absence of fraudulent intention would be inferred. A general intention to cheat the public is not