2()4f MINES AND MANUFACTURES 6F THE EAST INDIES; 



Analyfis of fpi- "flatter. The muriatic folulion, during evaporation, depofiteJ 

 4crs' webs. fulphate of lime. When fpiders* webs were incinerated in an 

 open vefTel, the afhes were found to contain fulphate of lime, 

 muriate of foda, and carbonate of foda. Muriatic acid ap- 

 plied to the refidue took up more fulphate of lime; and when 

 this folution was treated with ammonia and afterwards with 

 pot-afh, it gave oxide of iron, a little alumine, and fome lime. 

 The undifTolved part was (ilex. 



9. Spiders* webs were almoft totally diflblved in nitric acid 

 amounting to fix times their weight ; carbonic acid and ni- 

 trous gas being difer^^aged. The folution when evaporated 

 let fall cryftals of fulphatfe of lime, and by continuing the 

 evaporation, the yellow, bitter, deliquefcent matter, which 

 Welter calls amer, was afforded. 

 Component Hence the author concludes that fpiders' webs are compofed 



parts. Q^^ j^ ^ brown extracl foluble in water, and not changeable 



in the air ; 2. A refinous extract foluble in alcohol, and very 

 deliquefcent; 3. A fmal! quantity of alumine; 4. Sulphate of 

 lime; 5. Carbonate of foda; 6. Muriate of foda ; 7. Carbon- 

 ate of lime; 8. Iron; 9. Silex. The author thinks that the 

 earths and earthy falts may be derived from the local fituation 

 ' of thefe infers, and that it is^ probable that the webs of garden 



fpiders may not afford theni. The two conftant produ6ls to 

 which he demands particular attention, are thofe obtained 

 from the aqueous and alcoholic folutions. He thinks it de- 

 firable to try their medical powers feparately. He fuppofes 

 the refinous matter to be the fame fubflance as under other 

 circumflances forms the fpiders' fiik, and the wax which Mr. 

 Accum has elfewhere mentioned as one of their produfts. 



XII. 



Information on the Mines and Manufactures of the Eaji Indies, 

 and* other Subjedis, Bj/ J. Machlachlan, Efg. of CaU 



cutta,* 



SIR, 



Account of oHOULD you think the enclofed receipts for dying the 



fomc receipts beautiful reds of the Coromandel coaft can be of any ufe to 



for dying. J 



* S$c, Alts, 1804 J for which the filvcr medal was given, 



the 



