210. Although the cost of any article may be reduced in its ultimate analysis to the quantity of labour by which it was produced; yet it is usual, in a certain state of the manufacture of most substances, to call them by the term raw material. Thus
263. On examining the analysis which has been given in chapter XIX of the operations in the art of pin-making, it will be observed, that ten individuals are employed in it, and also that the time occupied in executing the several processes is very
The Latrobe Steel Company make a high-speed steel without tungsten, its red-hardness properties depending on chromium and cobalt instead of tungsten. It is known as P. R. K-33 steel. It does not require the high temperature of the tungsten steels, h
A mixture of fireclay and sand will be found very satisfactory for closing up the boxes, and by observing the appearance of the work when taken out we can gage the suitability of the methods employed, for unless the boxes are carefully sealed the wo
The carbon- and nickel-steel gears are carburized separately owing to the difference in time necessary for their carburization. Practically all printed information on the subject is to the effect that nickel steel takes longer to carburize than pla
These steels are recommended for boring, turning and planing where the cost of high-speed seems excessive. They are also recommended for hard wood knives, for roughing and finishing bronze and brass, and for hot bolt forging dies. This steel cannot
Commercial steels of even the simplest types are therefore primarily alloys of iron and carbon. Impurities and their remedies are always present: sulphur, phosphorus, silicon and manganese--to say nothing of oxygen, nitrogen and carbon oxide gases,
20. Whenever the work to be done requires more force for its execution than can be generated in the time necessary for its completion, recourse must be had to some mechanical method of preserving and condensing a part of the power exerted previously
140. In this species of copying there exists but little resemblance between the copy and the original. It is the cross-section only of the thing produced which is similar to the tool through which it passes. When the substances to be operated upon
163. The economical principles which regulate the application of machinery, and which govern the interior of all our great factories, are quite as essential to the prosperity of a great commercial country, as are those mechanical principles, the op
77. The precision with which all operations by machinery are executed, and the exact similarity of the articles thus made, produce a degree of economy in the consumption of the raw material which is, in some cases, of great importance. The earliest
298. There are many enquiries which ought always to be made previous to the commencement of the manufacture of any new article. These chiefly relate to the expense of tools, machinery, raw materials, and all the outgoings necessary for its producti