Ph'ihmal'ic Society of Paris, 281 



prifoners of war might be introd-iced among a favage people 

 reduced to fiich a Itate of famine as to be obliged to fnfpend 

 their hunsfer bv diftending their ftomachs and intcflincs with 

 an earthy^fiibftance whieh has no other alimentary quality 

 than that of being friable. 



V'auquelinj being delirous of afcertaining the nature of this 

 earth, and whether it contained any thing nutritive, ana- 

 lyfcd, by the known means, fpecimens of it Iranfmitled to 

 liim bv C. Labillardiere. 



This earth is foft to the touch, and confifls of fmall fibres 

 eafy to be divided : it becomes red in the fire, and lofes 

 T-j-^ of its weight. It contains 37 parts of pure magnefia, 

 ^6 of filex, 17 of oxide, 3 or 4 of water, and 2 or 3 of lime 

 and copper. 



It .-ontains therefore no nutritive part, and can be confi- 

 dered only as a burthen — as a mechanical mean for fuf- 

 pending the pain oecafioned by hunger. 



The fame chemill read a notice on blue o.xide of iron. 

 This fabftancc, font to the Council of Mines by baron De 

 Molt, is of a bright bine colour: it prefents itfelf under the 

 form of fmall infulated malfes in the cavities or fifiures of 

 quartz and hard greenilh fteatites. It is fria!)le, but a little 

 Uliginous to the touch. It lofes its colour by the flame of 

 the blow-pipe, and then fufes into a greenifli white glafs. 



It lofes its col-our neither by acids nor by weak alkalies; 

 a circumftance which diftinguiihes it from /apis I z-uH and 

 prufiTiatc of iron. It communicates to the muriatic acid in 

 which it has been put to digefl, a faffron yellow colour, and 

 lofes a little of its own coloiir ; but it cannot be entirely de- 

 prived of its colour without difiblving it at the fame time: 

 nothing then remains but the fame quantity of filcx, which 

 icems to ferve it as matrix. 



In cxamininjr the muriatic acid which fened for this ope- 

 ration. It is feerTthat it has dilfolved alumine, lime, and oxide 

 of iron; bnt neither manganefe, fulphurated hydrogen, nor 

 phofphoric acid, fubflances to which fome might be inclined 

 to afcribe the blue colour of this oxide of iron, are to be dif- 

 covered in it. The caufe of the very remarkable colour of 

 this oxide, a colour which it has hitherto been impoflfible to 

 conmumicate to iron by any chemical mean?, fiill remains, 

 therefore, to be determined. It appears, however, that the 

 iron in this oxide is carried to a degree of oxygenation near 

 to a maxim nni. 



N'auquelin read alfo a note on the faline fubflance called 

 muriciate of Salzhourg. This matter, to which Ilaiiy has 

 giVL-n the name of gvyifrous muriate of foda, was alio fent 



to 



