48 Mac Culloch on Animals preserved in Amber. 



in these cases. The oil of amber, in all its most important 

 characters, resembles naphtha; and thus it might, (I priori, be 

 suspected, that the same influence which could render wood in 

 the form of jet (or coal), capable of yielding naphtha, might, 

 under analogous circumstances, so change a vegetable resin as to 

 cause it also to yield a species of naphtha instead of the resinous 

 essential oil. This probability, of the change of vegetable resin 

 into amber by long submersion in alluvial soils, is strengthened by 

 other analogous occurrences. 



In the submerged wood (brown coal of Bovey), a substance is 

 found, so intermediate in its chemical characters between vege- 

 table resin and asphaltum, that Mr. Hatchett has given it the very 

 expressive name of retinasphaltum. It appears to be a vegetable 

 resin, in which the change to amber, or to some analogous sub- 

 stance, is as yet so far incompleted that it retains the mixed 

 character of both. The same, or a similar substance, has been 

 found in other alluvial soils, as, for example, in the London clay 

 (of Highgate): and my analysis proves this to be of the same 

 chemical nature. In these instances, the incompleted change from 

 resin to amber, or to a substance, at least, of which the distilled 

 volatile produce would resemble naphtha, or the mineral essential 

 oil, holds an exact parallel to certain of the cases in which the 

 progress from brown coal, in the common vegetable fibre partially 

 bituminized, can be traced down to perfect coal, or to a substance 

 capable of yielding naphtha only on distillation. 



It is from these analogies that we may, perhaps, safely conclude, 

 that amber has been a vegetable resin converted to its present 

 state during the same time and by the same causes which have 

 converted common vegetable matter into jet, and, perhaps , ulti- 

 mately into coal. 



That it is found in the same alluvial soils with jet, is, perhaps, 

 too feeble an argument to deserve any weight ; but it is also one 

 which seems superfluous. Every circumstance which attends 

 amber strongly bespeaks its vegetable origin ; and nothing proves 

 it more strikingly than that which forms the main object "of this 

 communication. 



