of \ some of the Principles of Vegetables into Bitumen , &c. 399 
A. 200 grains of the Bovey coal, by distillation, yielded. Grains. 
1. Water, which soon came over acid, and afterwards 
turbid, by the mixture of some bitumen - 60 
2. Thick brown oily bitumen - - - - 21 
3. Charcoal - - - 90 
4. Mixed gas, consisting of hydrogen, car- j 
bonated hydrogen, and carbonic acid, j estimated at 29 
200. 
The charcoal, in appearance, perfectly resembled that which 
is made from recent vegetables. By incineration, about 4 grains 
of yellowish ashes were left, which consisted of alumina, iron, 
and silica, derived most probably from some small portion of 
the clay strata which accompany the Bovey coal. But it is very 
remarkable, that neither the ashes obtained from the charcoal 
of the Bovey coal, nor those obtained from the leaves of the 
Iceland schistus, afforded the smallest trace of alkali.* 
B. 200 grains of the Bovey coal, reduced to powder, were 
digested in boiling distilled water, which was afterwards filtrated, 
and examined; but I could not discover any signs of extract, 
or of any other substance. 
C. 200 grains were next digested with six ounces of alcohol, 
in a very low degree of heat, during five days. A yellowish- 
brown tincture was thus formed, which, by evaporation, afforded 
a deep brown substance, possessing all the properties of resin, 
being insoluble in water, but soluble in alcohol, and in ether ; it 
* This, as far as relates to the Bovey coal, has been also noticed by Dr. Milles. 
Phil. Trans. Vol. LI. p. 553. But wood, however long submerged, is not deprived of 
alkali, unless it has more or less been converted into coal ; for I have, since the reading 
of this Paper, made some experiments on the wood of the submerged forest at Sutton, 
on the coast of Lincolnshire, and have found it to contain potash. 
sF 
MDCCCIV. 
