of the Life and Works q/'M. Breguet. 209 



by uniting the study of rational mechanics and physics to the 

 precepts and examples of the two first artists in Europe. On 

 his return to Paris he shared in all the labours, and in all the 

 success of his father; and historical truth requires us to state, 

 that from that time their names should no longer be separated 

 in enumerating the services which they have rendered to the 

 sciences. 



When the Institute of France was newly organized, M. 

 Breguet, who had previously been admitted into the board of 

 longitude, was appointed a member of the Royal Academy of 

 Sciences. 



He had long before invented an escapement, entirely free, 

 and with a constant force, a fundamental question, which 

 comprehends all that is important and difficult in the art, but 

 which we cannot now explain, without multiplying technical 

 terms. He improved also the use of rubies and sapphires, 

 which contribute greatly to the precision and regularity of 

 motions ; and it is to him that we owe the methods of cutting 

 hard stones for this purpose. 



By a happy arrangement of the different parts, he succeeded 

 in simplifying the mechanism of repeating-watches, and in re- 

 ducing them to the smallest compass. It was then that he sub- 

 stituted in place of large and inconvenient bells elastic plates, 

 which, when struck at one end, emitted a soft and continued 

 sound. The apertures became useless, and the sound was better 

 heard when the case was more completely shut. We may give to 

 these vibrating plates such dimensions, that the effect becomes 

 equal to that of the most sonorous instruments. The mixture 

 and the concord of the harmonic sounds give to these vibra- 

 tions a particular character. This invention of spring-bells, 

 due to M. Breguet, has found many applications. In France, 

 and in England, it has> given rise to a new and productive 

 branch of trade, which has extended itself to all countries un- 

 der the most varied forms. * 



An attempt had been made to measure high temperatures, 



* The editor of the BibL Universelle remarks, that this art had its ori- 

 :, gin in Geneva, and that it was brought out in the fabrication of musical 

 boxes. An account of the mechanism of thesie boxes will be found in the 

 article Horology, in the Edinburgh Encyclopedia, vol. xi. p. 175. — Ed. 



