223 
tered in small pieces, and sometimes even accumulated in heaps. 
Hoffman supposes the amber here to have been formed by the oil 
of the wood flowing from subterranean heat, like the oil of petro- 
leum, and passing through the bed of pyrites, which lay underneath, 
thus becoming impregnated with the acid of the vitriol, and thereby 
obtaining its peculiar nature and appearance. 
The opinion of Neuman very nearly agreed with that of Hoff- 
man, he supposing the amber to be formed by the combination of 
the oil of petroleum with a fine earth held in solution by the acid 
of vitriol. 
The frequent existence of small insects, and of vegetable matters, 
in the midst of its masses, presents a considerable difficulty to 
those who consider it entirely as a mineral production. Breynius, 
however, in the paper already mentioned, remarks that the pre- 
sence of these foreign matters is not inconsistent with the idea of 
its subterranean formation; he observing that many insects pene- 
trate beneath the surface of the earth, to deposit their eggs, to 
change their skin, or to relinquish life ; and that vegetable matters 
are also carried beneath the surface by various insects, who thus 
retire into the earth. But when it is considered that insects make 
their way but a little depth below the surface, and that the amber 
is found at considerable depths, there seems but very little proba- 
bility that these substances had become imprisoned in this way. 
Besides, the substance which appears to be the most common matrix 
of amber, is bituminous wood, and very unlikely to be thus visited, 
it being a circumstance deserving of notice, not only in reference 
to this particular circumstance, but as an important general fact, 
that bituminous impregnations are so unfriendly to animal life, that 
no living creature has ever been found in peat, or in any other 
stratum of the bituminous kind. 
This particular circumstance has been remarked by several of 
the most intelligent writers on the history of these substances. 
