TIN. 
535 
tients derived their tin is an interesting historical 
point which has not as yet been satisfactorily 
settled. Some suppose the Cassiterides, now called 
Scillae, were the islands from whence the Phenician 
merchants drew their tin, and that Cornwall fur- 
nished them with a considerable quantity ; while 
others think the antients were indebted for this use- 
ful metal to some islands situated on the coast of 
Galicia, in Spain. 
Tin is of all metals (quicksilver of course ex- 
cepted) the most fusible, since it requires only twice 
the heat of boiling water to melt it. It possesses so 
little ductility that it cannot be drawn into wire, 
though it may be extended between rollers or beat 
into thin plates. The crackling noise which tin 
makes when it is bent in different directions, is a 
property peculiar to this metal, and is supposed to 
be owing to the arsenic which may be mixed with 
it, since those operations by which this pernicious 
semimetal is separated from tin, destroy its crackling 
noise. 
Tin is applied to many purposes in the arts. It 
is mixed with quicksilver in order to make looking- 
glasses, and is particularly serviceable as a coating 
to many of our vessels. Those metallic plates gene- 
rally called tin, are merely plates of iron which have 
been dipped in this metal, and which are afterwards 
formed into a variety of utensils used for culinary 
and other purposes. Before the sheets of iron are 
tinned they are cut to a proper size, and steeped in 
a solution of sal ammoniac, or in an acid liquor pio- 
