Page:The Kinematics of Machinery.djvu/272

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250 KINEMATICS OF MACHINERY.

each part, to indicate its motion. The symbols employed are arrows of various kinds, full lines, dotted lines, brackets, crosses, hooks, and so on. It is certainly possible to interpret the action of the machine by the aid of the signs when the meanings of these have once been completely mastered. Notwithstanding this the method has never been used. No notice was taken of it by those practically interested in machinery, and by this want of attention they added unconsciously to the great irritation which displayed itself in the work which Babbage published shortly before his death- In this he struck about him most vehemently, like Timon of Athens with his spade, accusing his contemporaries of their want of comprehension and appreciation of his work. Without in the least depreciating, however, his most important labours in other directions, it must be said that the cause of the non-acceptance of his system of notation was due to its own defects, and not to those of the public.

What the symbolic memoranda of Babbage express, and were intended to express, is not the essential constitution of the machine, its different parts scientifically defined and recognizably indicated by the stenographic symbols, but merely the general nature of the motion of those pieces which were themselves described at length or by their names in the usual manner. We learn whether such and such a piece turns backwards or forwards, moves continuously or disconttnuously, uniformly or with varying velocity, and in cases where there is turning about axes we have the velocity-ratio and so on, given. It is at once evident, however, that under this system mechanisms of completely different constructions might be repre- sented by one and the same set of symbols. These extend merely to the external conditions accompanying certain characteristics of the single organs, not to their full meaning ; they form simply a concise description of the action of the machine, not in any way showing its dependence upon general fundamental principles. If the symbols proposed by Mr. Babbage were placed upon the neces- sary drawing of the machine itself, they would express their meaning much more clearly than when used in the more abstract

form of a table.*

  • In a small pamphlet of half-a-dozen pages published in 1857 Mr. Babbage again

proposed a very complicated " Mechanical Notation," no doubt the offspring of his own requirement in connection with his machines ; but here he appears to have