a8o AJfa-ying of Sllt'cri, 



ignorance or cnieltv. C. Pelletan, on the other hand, en- 

 deavours to encourage them to undertake another operation^ 

 which may be ufcful, and which mifplaccd timidity often 

 prevents from being praiSlifed ; it is that of hroncholoviy, or 

 opening the tracheal artery. Whenever any body capable 

 of flopping refpiration is introduced into that canal, it may 

 be boldly opened, in order to get rid of it. 



C. Portal has revived the ideas, which he announced in 

 1783, on the treatment of that kind of apoplexy called ytroz/^j 

 tliat is to fay, of that kind during which the face remains 

 pale and livid. He has proved that emetics, generally ad- 

 miniflered in fuch cafes, are the more inefficacious, as in 

 every kind of apoplexy the ftomach is palfied ; and that, be- 

 fides, it has appeared bv all bodies which have been opened, 

 that in the fcrous apoplexy, as well as in others, there are 

 accumulations of blood in the brain. He does not hefitate, 

 therefore, to recommend bleeding for the one as well as for 

 the other ; and he has proved by praftical obfervations that 

 it has often fucceedcd» 



C. Duhamel has been employed in improving the art of 

 affaying filver, or of feparating it from the lead it contain?. 

 For this procefs, on a fniall fcale, refiners employ fmall cups 

 of well lixiviated bone-aflies called cupclls, which abforb the 

 lead as it vitrifies, and leave the filver pure: on a large fcale 

 they employ cupells formed of wood-afhes ; but, befides their 

 being expenfive, they are attended with feveral inconve- 

 niences. C. DuhameU aficr remarking that the litharge, 

 or glafs of lead, may be feparated in proportion as it is 

 formed, without cauiing it to be abforbed by the cupells, 

 propofes that thefe \circ!s fliould be made of founders fand 

 mixed with clay ; that the I'urface of them Hiould be covered 

 with a ftratum of aflies; that the blaft of the bellows fliould 

 be direiSled on the fluid lead to accelerate the oxydation ; and 

 that the litharge fliould be made to run off by a groove 

 formed in tlic edge of the cupell, and which ought to be 

 duK lower in proportion as the bath finks down. 



C. Lacepede read an ingenious memoir on fome pheno- 

 mena refpe£ting the flight and vifion of birds. He took, as 

 the obje(3; of his obfervations, the eagle and man-of-war' 



bird J 



J 



