OS vee 
APPENDIX. * 
No. I. 
SPECIFIC GRAVITY OF SOME OF THE FOREGOING RESULTS. 
S many of the artificial limeftones and marbles produced in 
thefe experiments, were poflefled of great hardnefs and com- 
pactnefs, and as they had vifibly undergone a great diminution 
of bulk, and felt heavy in the hand, it feemed to me an object of 
fome confequence to afcertain their fpecific gravity, compared 
with each other, and with the original fubftances from which 
they were formed. As the original was commonly a mai{s of 
- chalk in the lump; which, on being plunged into water, begins 
to abforb it rapidly, and continues to do fo during a long time, 
fo as to vary the weight at every inftant, it was impoffible, till 
the abforption’ was complete, to obtain any certain refult; and 
to allow for the weight thus gained, required the application of 
Nol, VI.—P. I. Z a 
