mer generations has given rise in the present age to children of a larger growth. Arts have grown only as machinery for the accomplishment of their objects has developed, and machinery has waited on the development of the metals composing it. The civilisation of to-day would not have been possible if the successors of Tubal Cain had not been like him, instructors "of every artificer in brass and iron."

CHAPTER XV.

METAL WORKING.

WE referred in the last chapter to the fact that metal when it came from the melting and puddling furnace was formerly rolled into sheets; but, when the manufacturers and consumers got these sheets then came the severe, laborious work by hand of cutting, hammering, boring, shaping and fitting the parts for use and securing them in place.

It is one of the glories of this century that metalworking tools and machinery have been invented that take the metal from its inception, mould and adapt it to man's will in every situation with an infinite saving of time and labour, and with a perfection and uniformity of operation entirely impossible by hand.

Although the tools for boring holes in wood, such as the gimlet, auger, and the lathe to hold, turn and guide the article to be operated on by the tool, are common in some respects with those for drilling and turning metal, yet, the adaptation to use with metal constitutes a class of metal-working appliances distinct in themselves, and with some exceptions not interchangeable with wood-working utensils. The metal-working tools and machines forming the subject of this chapter are not those which from time immemorial have been used to pierce, hammer, cut, and shape metals, directed by the eye and hand of man,

but rather those invented to take the place of the hand and eye and be operated by other powers.

It needs other than manual power to subdue the metals to the present wants of man, and until those modern motor powers, such as steam, compressed air, gas and electricity, and modern hydraulic machinery, were developed, automatic machine tools to any extent were not invented. So, too, the tools that are designed to operate on hard metal should themselves be of the best metal, and until modern inventors rediscovered the art of making cast steel such tools were not obtainable. The monuments and records of ancient and departed races show that it was known by them how to bore holes in wood, stone and glass by some sharp instruments turned by hand, or it may be by leather cords, as a top is turned.

The lathe, a machine to hold an object, and at the same time revolve it while it is formed by the hand, or cut by a tool, is as old as the art of pottery, and is illustrated in the oldest Egyptian monuments, in which the god Ptah is shown in the act of moulding man upon the throwing wheel. It is a device as necessary to the industrial growth of man as the axe or the spade. Its use by the Egyptians appears to have been confined to pottery, but the ancient Greeks, Chinese, Africans, and Hindoos used lathes, for wood working in which the work was suspended on horizontal supports, and adapted to be rotated by means of a rope and treadle and a spring bar, impelled by the operator as he held the cutting tool on the object. Joseph Holtzapffel in his learned work on Turning and Mechanical Manipulation, gives a list of old publications describing lathes for turning both wood and metal. Among these is Hartman Schapper's book published at Frankfort, in

1548. A lathe on which was formed wood screws is described in a work of Jacques Besson, published at Lyons, France, in 1582.

It is stated that there is on exhibition in the Abbott museum of the Historical Society, New York, a bronze drinking vessel, five inches in diameter, that was exhumed from an ancient tomb in Thebes, and which bears evidence of having been turned on a lathe. It is thought by those skilled in the art that it was not possible to have constructed the works of metal in Solomon's Temple without a turning lathe. One of the earliest published descriptions of a metal turning lathe in its leading features is that found in a book published in London, in 1677-83, by Joseph Moxon, "hydographer" to King Charles II., entitled, Mechanical Exercises, or the Doctrine of Handy Works. He therein also described a machine for planing metal. Although there is some evidence that these inventions of the learned gentleman were made and put to some use, yet they were soon forgotten and were not revived until a century later, when, as before intimated, the steam engine had been invented and furnished the power for working them.

Wood-working implements in which the cutting tool was carried by a sliding block were described in the English patents of General Sir Samuel Bentham and Joseph Bramah, in 1793--94. But until this century, and fairly within its borders, man was content generally to use the metal lathe simply as a holding and turning support, while he with such skill and strength as he could command, and with an expenditure of time, labour and patience truly marvellous, held and guided with his hands the cutting tool with which the required form was made upon

or from the slowly turning object before him. The contrivance which was to take the place of the hand and eye of man in holding, applying, directing and impelling a cutting tool to the surface of the metal work was the slide-rest. In its modern successful automatic form Henry Maudsley, an engineer in London, is claimed to be the first inventor, in the early part of the century. The leading feature of his form of this device consists of an iron block which constitutes the rest, cut with grooves so as to adapt it to slide upon its iron supports, means to secure the cutting tool solidly to this block, and two screw handles, one to adjust the tool towards and against the object to be cut in the lathe, and the other to slide the rest and tool lengthwise as the work progresses, which latter motion may be given by the hand, or effected automatically by a connection of the screw handle of the slide and the rotating object on the lathe.

A vast variety of inventions and operations have been effected by changes in these main features. Of the value of this invention, Nasmyth, a devoted pupil of Maudsley and himself an eminent engineer and inventor, thus writes: "It was this holding of a tool by means of an iron hand, and constraining it to move along the surface of the work in so certain a manner, and with such definite and precise motion, which formed the great era in the history of mechanics, inasmuch as we thenceforward became possessed, by its means, of the power of operating alike on the most ponderous or delicate pieces of machinery with a degree of minute precision, of which language cannot convey an adequate idea; and in many cases we have, through its agency, equal facility in carrying on the most perfect workmanship in the interior