[ 469 ] 
merly been publifhed concerning the fpecific Gravity 
of Diamonds, is not to be depended upon j I hope 
a fhort Account of thefe Experiments will not be 
■unacceptable to you, efpecially as I do not find the 
leaft Notice taken of the fpecific Gravity of Dia- 
monds in any of the Tables published in the Phi- 
lofophical Tranf all ions. 
In the Account the Honourable Mr. Beyle has 
given of Diamonds (as publifhed by Dr. Shaw , in his 
Abridgment of that Gentleman's Philofophical 
Works *), he relates it “ as the Opinion of a famous 
<c and experienced Cutter of Diamonds, that fome 
€c rough Diamonds were confiderably heavier than 
“ others of the fame Bignefs, efpecially if they were 
“ cloudy or foul j and Mr. Boyle mentions one that 
11 weigh’d 8 Grains and —g 5 which, being carefully 
weigh'd in Water, according to the Rules of 
“ Hydroftatics, proved to an equal Bulk of that 
“ Liquor, as 2 || to 1 ; fo that, as far as could 
<e be judged by that Experiment, a Diamond weighs 
“ not thrice fo much as Water." And yet, in this 
Table of fpecific Gravities, that of a Diamond is faid 
to be to Water as 3400 to 1000, or as 3, 4. to 1 ; 
and therefore, according to thefe two Accounts, there 
fhould be fome Diamonds, whofe fpecific Gravity 
(hall differ nearly the •§- from others $ which I am 
perfuaded, is a much greater Difference than could 
be expe&ed in any Bodies of the fame kind, or that 
which, on a more nice Examination, will be found 
to be in Diamonds. 
The 
* Pag. 83. Vol. V. new Edition of Mr. Boyle ' s Works in folio, 
Ooo 
