364 
Tin, 
our tin from Holland ; for, if w'e may believe an author 
of great note,— u in Holland every tin founder has English 
stamps, and whatever his tin be, the inscription, block tin, 
makes it pass for English*.” This foreign adulteration 
of English tin may be the reason that Musschenbroeck , 
who was many years professor of natural philosophy at 
Utrecht, puts the specific gravity of what he calls pure 
tin equal to 7320, but that of English tin, and he has 
been followed by Waller ins, equal to 747 If ; for it will 
appear presently, that such sort of tin must have contain- 
ed near one tenth of its weight of lead. 
Weight of a cubic foot of English tin, according to 
different authors. 
Cotes, Ferguson, Emerson 7320 oz. avoir, 
Boerhaave’s Chem. by Shaw 7321 
M usschenbroeck and W allerius 7471 
Martin 7550 
From the following experiments it may appear proba- 
ble, that not one of these authors, in estimating the spe- 
cific gravity of tin, has used the purest sort, but rather a 
mixture of that with lead, or some other metal. 
A block of tin, w r hen it is heated till it is near melting, 
or after being melted, and before it becomes quite fixed, 
is so brittle that it may be shattered into a great many long 
* Newman’s Chem. by Lewis, p. 89. 
jMusschen. Ess. de Phys. 1739. French Trans. Wallerii 
Min. Vol. 1. p. 154. There is a very good table of specific gravi- 
ties, published in the second volume of Musschenbroeck’s Intro - 
ductio ad Philosofihiam Naturalem , 1763, in which the author does 
more justice to English tin, putting the weight of a cubic foot of 
the purest sort equal to 7295 avoir, oun. One specimen of the 
purest sort of Malacca tin gave 7331, and another 6125 ounces a 
cubic foot, which is the lightest of all the tins which he ex- 
amined. 
