C 425 ] 
fubftances ; faid to have been formerly taken by Mr. 
Reynolds in the Tower of London. This gentle- 
man was the fame who compofed feveral tables re- 
lating to the price of Gold and Silver, which were 
publifhed in a book entitled The Secrets of the 
, Goldfmittis Art , at London 1676 , in oftavos Thefe 
weights are exprefled in decimals of an Aver- 
dupois Pound, are carried to 8 places of figures, 
and feem to have been carefully and accurately col- 
lected. I have therefore in the following tables re- 
duced them to the common form, in order to give 
them their proper authority with the reft. 1 am 
ignorant whether thefe weights were ever before 
printed or not, neither can I give any account, after 
what particular manner the experiments were made, 
from which they were taken. They were commu- 
nicated to me from the regifter-books of the Royal 
Society 5 and I fliall only obferve, that the abfolutc 
weight here afligned of a cubic inch of common 
water does not differ more than a fmall fraction of 
a grain, from the weight of the fame afterwards 
determined by Mr. Ward of Chejler. 
The Rhilofophical Society , meeting at Oxford , 
directed feveral experiments to be made hydrofta- 
tically by their members, concerning the fpecific 
gravities of various bodies j which being digefted 
into a table, were by Dr. Mufgrave communicated 
to the Royal Society the 21 st day of March 16 84. 
foon after which they were printed in the 169 th num- 
ber of the P hilofophical Tr anfaPlions . Thefe experi- 
ments were, according to Dr. Mufgrave , made by 
Mr. Cafwell and Mr. Walker : they are all originals, 
K k k 2 and 
