382 
had retained a few frail portions of their woody fibres, the spaces 
between which were filled up with chalky earth.” Mr. Bass, who 
acted as Surgeon on board the Reliance, and from whose accurate 
examination the above account is taken, was told, from good autho- 
rity, that when the trees were in a complete state, the diameter of the 
dead wood of the stem, that rose immediately from the stony part, 
was equal to the diameter of that part ; and also that a living leaf 
was seen upon the upper branches of one of them. Mr. Bass was 
induced to place these altered vegetable substances amongst petri- 
factions, although, he says, no strict analogy could be discovered 
between them and the subjects usually met with of this kind ; this 
gentleman acknowledging, at the same time, the great difficulty of 
accounting for this wonderful change which had taken place in the 
lower parts of the stems of these trees. 
If this ingenious and intelligent observer found himself incapable 
of explaining the mode in which this change had been accomplished, 
it is not to be expected that even the attempt should be made by 
one not possessing the advantage of examining the substances them- 
selves, nor of ascertaining their relative situation with the sur- 
rounding substances. 
In the Philosophical Transactions is the description of a pheno- 
menon which seems to bear some slight resemblance to that which 
has been just described, and which also is not capable of being 
explained, by any of those laws on which the various processes of 
petrifaction appear to depend. It is thus related : 
“ In a close of Mr. Purefoy, near his house, called JVadley, a mile 
from Farringdon, in Ferks, there grows an elm, which hath now lost 
the top, and is grown hollow, containing near a ton of timber. From 
the but of the same tree, one of the spreading claws, having been 
formerly cut off with an axe, that part of the but, from whence the 
same was severed, being about 1^ foot above ground, and inward 
within the trunk of the tree, hath contracted a petrified crust, about 
