225 
The opinion of Mr. Dalechamp, as we have already seen, is, that 
amber is a bituminous substance, which, exuding in a soft and nearly 
fluid state, from clefts in the earth where bituminous strata exist, has, 
during its soft and tenacious state, inviscated and enveloped these 
different extraneous bodies. Against this opinion there does not exist 
any objection, since it is not at all difiicult to conceive, that amber 
may be the solid form which the transparent fluid naphtha assumes 
from inspissation under certain circumstances, as asphaltum may be 
considered to be the result of a similar change effected on petroleum. 
It is true that I have considered it as probable, that petroleum, 
an opaque and dark-coloured substance, is naphtha changed by 
having suffered a degree of inspissation; it may therefore appear 
contradictory to suppose a transparent substance like amber to be 
likewise the result of the inspissation of naphtha. But, as has been 
already remarked with respect to the probable change of naphtha 
into petroleum, that change is not effected merely by inspissation, 
but by a separation and a change in the proportion of the consti- 
tuent principles, hydrogen having escaped, and charcoal having 
been deposited. But most certainly there is nothing 4o contradict 
the supposition, that naphtha is also susceptible of a simple evapo- 
ration and consequent inspissation, similar to that which the fixed oils 
undergo, from the long continued application of a gentle heat. 
If amber were gum or resin which has undergone the change of 
bituminization, the matters which it contains should certainly also 
have suffered a similar change. In the few pieces in my own pos- 
session, as well as in all others which I have seen, except in one 
instance, which I shall presently notice, the insects appear not to 
have suffered the least change, even in their colours, which surely 
must have been the case, had they been macerating in the softened 
mass which contains them, during such a change ; although, from 
the difference of their nature, they might be entirely exempt from 
the other effects of the bituminizating process. 
VOL. I. 
G G 
