120 On Animal Cotton * 



arising from the red salt ; for the new solution which thence 

 results is still precipitated red, though less intense : so that, 

 if these operations were repeated several times on the same 

 platina, it would at length be freed from this foreign metal. 

 The authors found also another method of separating this 

 metal from platina : it consists in dissolving the red salt 

 in boiling water, and mixing with it, as soon as it is dis- 

 solved, caustic potash. The liquor then becomes turbid, 

 and there are formed in it green flakes, which when washed 

 and heated give the metal again. The pale yellow precipi- 

 tate of platina, treated in the same manner, presented no- 

 thing of the same kind. 



It is then proved by their experiments, that there exists 

 In crude platina a new metal which communicates to the 

 triple salts of platina the red colour which is almost always 

 peculiar to them. As this metal is little susceptible of al- 

 teration by the agents employed to purify platina on a large 

 scale, the authors suspected that traces of it more or less 

 abundant ought still to be found in it; and this suspicion 

 was confirmed by experience, 



They found it in platina purified by C. Jannety and 

 Necker Saussure in almost as great quantity as in crude 

 platina; which induced them to say that in all probability 

 they had not yet met with this metal in a state perfectly 

 pure. 



C. Vauquelin and Fourcroy terminate their memoir by 

 recapitulating briefly the different results to which they were 

 conducted, and by saying that they suspect that the new 

 metal existing in platina enters conjointly with the latter 

 into the composition of the palladium announced by Mr. 

 Chenevix. 



They promise to continue their labour, and to procure a 

 greater quantity of the new metal for the purpose of sub- 

 jecting it "to new experiments, that they may make them- 

 selves better acquainted with iis" properties, and particularly 

 to discover means more proper for purifying platina than 

 those hitherto known. 



XXI. On Animal. Cotton, and the Insect which produces it. 

 By M. Baudry des Lozieiies. 



Dome successful experiments have been made in America 

 and the West Indies to preserve and increase the insect 

 known there by the name of fly-carrier, which produces an 



animal 



