[ 7«9 ] 
given the weight of its contents. The two firft differ 
from each other by almoft 5! modern Roman ounces, 
which is nearly the one-and-twentieth part of the 
whole weight, though they both meafured up to the 
fame part of the neck. The weight of water given 
by Psetus, is deficient of the mean weight of Auzouf s 
meafures by 3 Troy ounces; and that given by Vil- 
lalpandus exceeds the dime by a ; therefore they 
mud both have ufed bad ballances. 
Auzout meafured this veffel twice, with the water 
of Trevi. His greater weight of the water is 63024 
Paris grains, his leffer 62760 (7). 
Picard found a cubic Paris foot of fpring water to 
weigh 641326 Paris grains (8); and that foot con- 
taining 2o8p,6p cubic London inches, Auzoufs 
greater weight will give 205,36 fuch inches for the 
Solid content of the congius, his leffer 204!. 
According to Picard’s experiment, a cubic London 
inch of fpring water fhould weigh but 251 i Troy 
grains ; whereas, according to Snellius, it fhould 
weigh above 254 (p). 
Our countryman Wybard made many experiments 
to difcover the weight of water (1), from which the 
weight of a cubic inch of rain water fhould be 253 
Troy grains. His experiments feem to have been 
made with great attention, and his inch muff have 
been that of the iron ftandard, which I have already 
(7) See the paper De Menfuris, above quoted, p. 366. 377, 
of the fulio edit, where Picard gives thefe weights as Auzout s, 
without any farther account of them. 
(8) Ibidem. 
(9) Snellius, in Eratofthene Batavo, p. 155. 
(1) See Wybard’s Tadtometria, from p. 269 to p. 287. 
5 I 2 -(hewn 
