27 & 'Amber. [Book VI t 



but the quantity it diflfolves is very fmall. When 

 applied to the flame of a candle it readily takes fire, 

 and burns with a bright white flame and thick fmoke, 

 and leaves a confiderable quantity of charcoal. Am- 

 ber expofed to heat, without the action of flame, 

 foftens and fwells very considerably. Diftilled in a 

 retort by a heat gradually raifed, it affords a watery 

 fluid of a red colour, manifeftly acid j this acid fpirit 

 retains the flrong fmell of amber; an acid volatile 

 fait afterwards pafles over, which cryftallizes in fmall 

 white or yellowiih needles in the neck of the retort. 

 This fait is fucceeded by a white and light oil much 

 refembiing naphta ; by continuance of the procefs, and 

 in proportion as the heat is increafed, the oily matter 

 which comes over is coloured and more vifcid, like 

 petroleum. What remains at the bottom of the retort 

 is a black mafs refembiing afphaltum. It appears, 

 therefore, from diftillation, that the analogy of arnber 

 with the other bitumens is very ftrong. 



A gentle heat is fufficient to raife the concrete vo- 

 latile fait of amber, and care muft be taken to regu- 

 late it fo as not to force up the oil, when it is required 

 to have the fait in a feparate ftate. This faline matter 

 was for feme time fuppofed to be an alkaline fait, but 

 has been fmce found to be an acid of peculiar pro- 

 perties, and capable of combination with alkalies, 

 earths, and metallic calces. 



, - Amber is ufually dug out of the earth, and abounds 

 particularly in the Pruffian dominions. Wood is 

 generally found near it, and it is therefore believed to 

 be of vegetable origin. Its analyfis feems to fhew, 

 that it confifrs of an oil rendered concrete by combi- 

 nation with an acid. The moft tranfparent fpecimens 

 ire ufijftlly found on the fea-fhore, particularly on the 

 {bores of the Baltic, in Ducal Pruflia. Amber is not 



always 



