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[Book IV.
there could have been no more inducement to be thus explicit than withthe rest; but being of the same nature as others, he would naturally beled to notice the difference. Some writers are incredulous of his havingever put it in practice, notwithstanding his assertions, and the particularshe has specified; and they further contend that his description was notsufficiently perspicuous to enable a person to make such a machine in hisown time, and is not now. To neither of these positions can we assent;and the latter, if true, does not affect the character of Worcester , eitherfor veracity or ingenuity, since the avowed design of the Century wasrather to enable himself than others to realize the inventions named.
The description appears not only that of a machine in actual use, andfrom which a similar one might have been made, but, as just intimated,some particulars are mentioned apparently with the sole view of distin-guishing it from other devices of the same kmd. Had he given a figurewe should have learnt more of the details, but not of the general plan.The nature of the force employed (the expansive power of steam) heshows in the clearest light; and its irresistible energy is admirably illus-trated by bursting the cannon: indeed, he could not possibly have se-lected any thing better adapted for the purpose. Few writers howeverbelieve the experiment was ever made, from the seeming difficulty ofclosing the broken end—a circumstance which, perhaps more^than anyother, has led people to doubt the accuracy of other of his Statements : andit must be admitted that if he is not to be believed in this, his assertions ingeneral must be received with great caution. But what great difficultyafter all was there in driving a plug tight into the smoothly bored althoughbroken end of a cannon, and securing the plug effectually in its place, byiron Straps and screws round the trunnions 1 Lest the idea of dangershould be connected with his apparatus in the public mind, he remarksthat he had a way of preventing his vessels from being exploded. Hementions at least three vessels; one, a boiler in which to generate steam,the others, to receive the water previously to its being raised.' A separateboiler shows that the apparatus was a modification of Porta’s and Kircher’s,(Nos. 1S7, 190)—and lest any one should suppose that the water was re-quired to be heated before it was elevated, he States distinctly that it wasnot: hence his device bore no resemblance to that of Decaus, (No. 188)—so far from it that the boiler, or “ one vessel rarefied by fire,” forced upforty times its contents “ of cold water.” It appears that the water wasraised forty feet only ; perhaps being limited to that height by local cir-cumstances, or by the building in which the apparatus was erected. Thepressure of steam in his boiler did not therefore much exceed 301bs. onthe inch. As the elevation exceeded that to. which the liquid could beraised by atmospheric pressure, he also takes occasion to notice distinctlythat it was not done by sucking; and in this he possibly may allude tosome such modes of raising water, viz. by using the steam only to producea vacuum, and to showthe difference ; for, by employing its elastic force,he could raise water at one lift, to any height, and his apparatus, insteadof a limited application, was adapted to mines and pits of every depth,and hence he appropriately names it “ a mostforcible way.” The receivingvessels were charged or filled “ one after another,” and the stream dis-charged from them was uninterrupted. One person only was required toattend to the fire under the boiler and “ to turn two cocks,” i. e. to admitsteam alternately into each receiver, so that when one was “ consumed ”or emptied, the contents of the other began to “ force ” or be forced up,and the empty one to “ fill ” or be refilled with cold water, “ and so sue-cessively.” The vessels were large, or it took a long time to fill them,