420 Scientific Intelligence. 
increased resistance due to the motion of translation of the bird. 
Air, like all movable bodies, possesses inertia, so that when acted 
. 
wing is continually acting on a new portion of the air, which, on 
cle, and a rapid motion is imparted to it, the strokes of the wing 
take place very slowly, sometimes only once a second in the cas¢ 
of & pigeon, instead of eight times a second, which is their normal 
tees ae Comptes Rendus, 121. agape 
2. ; Vermiculites : their Crystallographic and Ch mical rela- 
tions to the Micas, together with a discussion of the cause of the 
; b si 
ence (vii, 55, 1824), T. H. Webb described a mineral from Mill 
orcester, Mass., which has since been a mineralog!< 
* Abstract of a paper published in the Proceedings of the American Academy 
of Arts and Sciences, vol. ix, page 35; prepared Se tls Journal by the author. 
