TIN. 
melted in an open vessel, its surface is soon found to be 
covered with a grey powder, which is an oxide (21) of 
the metal, and is generally called dross. If the heat 
be continued, the colour of this powder becomes yellow. 
In this state it is known by the name of tin-putty, and 
is employed in polishing glass, steel, and other hard sub- 
stances. When the heat is very violent, the metal 
takes fire, and is converted into a fine white oxide, 
which is used to render glass opaque, for the forming of 
enamel. Oxide of tin is also an important article to 
dyers. It is employed by them, in large quantities, to 
give brightness to such colours as are used in forming 
scarlets and other reds : and to precipitate the colour- 
ing matter of other dyes. 
Tin is an essential ingredient in bell-metal) bronze, 
pewter, and various other compounds. It may be com- 
bined with lead, in any proportion, by fusion ; and this 
alloy is harder, and possesses much more tenacity than 
tin. The hardest alloy is a composition of three parts 
of tin and one of lead. The presence of the tin destroys, 
in a great measure, the noxious qualities of the lead. It 
is sometimes customary to tin copper vessels with this 
mixture, and it has been ascertained that such vessels 
are in no respects injurious. 
There are three kinds of pewter in common use. 
These are called plate, trifle, and ley petvter. The first, 
which is made into plates and dishes, is formed of tin, 
with a small proportion of lead and antimony (245). 
The second, or trifle petvter, which is made in somewhat 
different proportions, is used for the quart and pint pots 
of the publicans: and the ley petvter, which is formed of 
three parts of tin and one of lead, is manufactured into 
wine and spirit measures. 
Tin may be beaten into leaves or plates that are much 
thinner than paper. But, when it is thus worked, se- 
veral leaves must be joined together. They then sup- 
port each other, and yield to the hammer without 
tearing. These leaves are used for the silvering of glass 
globes, and the plating of other metals. Those that are 
