C 455 ] 
If there is no miflake in the gravity of what Dr. 
Freind calls Vitrum Venetum , it differs very re- 
markably from all other kinds of Glafs. 
I do not know whether the Jafper and Hyacinth 
fpurious of J.C. are to be underftood as natural or 
, artificial Gemms. 
TABLE IV. 
Of Stones and Earths . 
Sardachates. J.C. 
Lapis fciffilis csruleus. Mufschenbr . (qu. 
if not the fame experiment mentioned 
before pag. 447. a blew Jlate with finning 
particles, jf. C.) . 
Cornelian. Boyle. 
Do. J.C. . : 
A Hone. J.C. . . 
D°. to let razors on. Harris. 
Marmor. Be tit us. (probably fome miftakc 
in the experiment.) . . 3.937. 
Marble. Reynolds. 
Do. white. Hauksbee. 
Do. white Italian, of a clofe texture vi- 
fbly. 
D°. white. Boyle, fine. Ward. C. 
D°. white Italian, tried twice. Oxford 
Soc. . • 
Do. black Italian. Oxford. Soc. veined. L. 
D°. black. Hauksbee y 
Do. Parian. L. 
Lapis Amianthus, from Wales. J. C. 
Turquoife, one of the old rock, very perfed. 
Hauksbee. . 
Turcoife Stone. J.C. . , 
O o o 
3.5-00 
3.290 
2.f62 
3.288 
2.96O 
3.026 
2.765 
2 .7l8 
2.710 
2.7 0 7 
2 . 7 0 4 
2.683 
2.560 
2.913 
2.90 8 
2.508 
Lapis 
