Author Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1825 edition. Excerpt:... IV --LOCO-MOTIVE ENGINES. In my investigations respecting loco-motiva engines, I shall confine myself wholly to those which effect their progressive motion by means of the adhesion of their wheels upon the rails; the only engines of that kind at present in use which do not, are those of Mr. BlenKinsops, at Leeds, with the rack-rail; and as I haVe not had any opportunity of ascertaining their performance by the test of experiment; I shall not, therefore, attempt to give any opinion of their utility, compared with the other, founded only on report or on bare supposition. I have before explained the nature of the action of the engine-wheels upon the rails; and the principle by which the loco-motion is effected; the great importance of knowing the precise amount of that adhesion, whereby we may be able to calculate, with certainty, upon what inclination of road, and with what number of carriages, the engines can effect their progressive motion, will be very evident, as, upon that, the whole system of their action is regulated. This may either be ascertained by continued observation of their performance upon certain lines of roads; or, it may be made the subject of direct experiment. The great variation in the amount, arising from the surface of the rail presenting more or less adhesion to the wheels, in different states of the weather, renders it difficult to subject the engines to experiments at all the various changes; and almost compels us to have recourse to the two extremes in order to obtain a mean result. I shall, therefore, give the particulars of two experiments, one in the most favorable, and the other in the most unfavorable state of the rails. When the surface of the rails and wheels are either quite dry or completely wet, the...