BIOGRAPHICAL INDEX 



at Haling, England, May 4, 1825; died at East- 

 bourne, June 29, 1895. English biologist. Fore- 

 most English champion of Darwin's theory of 

 evolution, his active interest in the subject be- 

 ing largely responsible for the early acceptance 

 of Darwin's conception. 



Huygens, Christian, ii, 218. Born at The 

 Hague, April 14, 1629; died there June 8, 1695. 

 A celebrated mathematician, physicist, and as- 

 tronomer. He was the inventor of the pendu- 

 lum clock. With his brothers he constructed a 

 telescope with which he discovered a hitherto 

 unknown satellite of Saturn. Later he adapted 

 the micrometer to the telescope, this being a me- 

 chanical device upon which the nice determina- 

 tion of minutes depends. One of his many 

 interesting papers sent to the Royal Society was 

 his "Rules Concerning the Motion of Bodies 

 after Mutual Impulse," in which the laws of 

 motion are stated in remarkably clear and con- 

 cise terms. 



Jackson, Dr. Charles Thomas, iv, 215. Born 

 at Plymouth, Mass., June 21, 1805; died at 

 Somerville, Mass., Aug. 29, 1880. American 

 physician and geologist. One of the claimants 

 to the discovery of etherization. Also claimant 

 to the invention of a telegraph similar to 

 Morse's. 



Jacquard, Joseph Marie, ix, 49. Born at Lyons, 

 France, July 7, 1752; died near Lyons, Aug. 7, 

 1834. French mechanic and inventor. He in- 

 vented the Jacquard loom about 1801. Modifica- 

 tions of this loom are still used extensively for 

 weaving designs and patterns. 



Jansen (or Zanss) Zacharias, ii, 77. A Dutch 



