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FORE:In no other branch of machinery has so much research and experiment been made during eighty years past as in steam machinery, and, strange to say, the greater part of this research has been directed to the details of engines; yet there has been no improvement made during the time which has effected any considerable saving of heat or expense. The steam-engines of fifty years ago, considered as steam-using machines, utilised nearly the same proportion of the energy or power developed by the boiler as the most improved engines of modern construction��a fact that in itself indicates that an engine is not the vital part of steam machinery. There is not the least doubt that if the efforts to improve steam-engines had been mainly directed to economising heat and increasing the evaporative power of boilers, much more would have been accomplished with the same amount of research. This remark, however, does not apply to the present day, when the principles of steam-power are so well understood, and when heat is recognised as the proper element to deal with in attempts to diminish the expense of power. There is, of course, various degrees of economy in steam-using as well as in steam-generating machinery; but so long as the best steam machinery does not utilise but one-tenth or one-fifteenth part of the heat represented in the fuel burned, there need be no question as to the point where improvements in such machinery should be mainly directed.Rapping plates, draw-irons, and other details of pattern-making are soon understood by observation. Perhaps the most useful suggestion which can be given in reference to draw-irons is to say they should be set on the under or bottom side of patterns, instead of on the top, where they are generally placed. A draw-plate set in this way, with a hole bored through the pattern so as to insert draw-irons from the top, cannot pull off, which it is apt to do if set on the top side. Every pattern no matter how small, should be ironed, unless it is some trifling piece, with dowel-pins, draw and rapping plates. If a system of draw-irons is not rigidly carried out, moulders will not trouble themselves to take care of patterns.

FORE:Lawrence laughed and departed with the assurance that Isidore should know soon enough. He spent the rest of the morning at the club, and after luncheon took his way gaily in the direction of Lytton Avenue.

FORE:"What is happening here is frightful; those men are also human beings, who had to do their duty as much as you!"