1 9 4 HER OES OF INVENTION AND DISCO VER Y. 



can only be combined in two ways on the same straight line, 

 yet the one can be put above and below the other, as well as 

 on its right side or its left side, and may be joined so that the 

 line connecting those centres may have an infinite number of 

 positions with respect to an horizontal line. 



CHARLES BABBAGE. 



The calculating machines of the late Mr. Babbage have at 

 different times excited much interest on the part of the public 

 and of scientific men. 



" Mr. Babbage," says a \vriter in the Encydopcedia Britannica, 

 "was a fellow student at Cambridge with Sir John Herschel 

 and Dean Peacock, and along with them contributed by his 

 writings and personal efforts to introduce into that university the 

 improved Continental mathematics. 



"A few years after leaving college, he originated the plan of 

 a machine for calculating tables by means of successive orders 

 of differences; and having received for it in 1822 and the fol- 

 lowing year the support of the Astronomical and Royal Societies, 

 and a grant of money from Government, he proceeded to its 

 execution. It is believed that Mr. Babbage was the first who 

 thought of employing mechanism for computing tables by 

 means of differences : the machine was subsequently called the 

 differ e7ice machined 



" In the course of his proceedings, Mr. Babbage invented a 

 mechanical notation (described in the Philosophical Transactions 

 for 1826), intended to show the exact mutual relations of all 

 the parts of any connected machine, however complex, at any 

 given instant of time. He also made himself acquainted 

 with the various machines used in the arts, with the tools 

 used in constructing them, and with the details of the Piosi 



