Tin. 
385 
up by one corner by a pair of pincers and dipped verti- 
cally into the tin, and when withdrawn is found beautiful- 
ly white and resplendent with the coating of this metal 
that adheres to it. This dipping is repeated three times 
for what is called single tin plate, and six times for the 
double plate. The plates are then only cleansed and sort- 
ed, and are fit for use. 
Some further particulars may be added from other au- 
thorities. 
In many manufactories the iron plates before tinning 
are cleansed by being immersed in large barrels full of a 
mixture of rye- flour and water, sometimes with verjuice 
by which fermentation has become very acid. In Bohe- 
mia the plates remain three times twenty-four hours in 
tubs filled with this acescent mixture, in three different 
states, after which they are washed, scoured with sand and 
water, and kept under water till just before they are used, 
to avoid rusting again. 
Attention is to be paid to the heat of the melted tin ; if 
too hot the plate comes out yellow. The plates are im- 
mersed quite wet into the melted tin, passing in their way 
through the melted suet which covers it. Just before 
dipping, some water is thrown on the melted suet, which 
causes a violent ebullition and makes the surface of the 
metal quite clean and bright. The plates when tinned 
are set up to drain, by which a number of drops of tin 
collect in small knobs at the lower part. These are taken 
off by a second immersion into a separate cauldron of tin, 
but only to the depth of a few inches, by which the drops 
of tin melt down and the whole tinning is made more uni- 
form in thickness. They are then cleansed with a rag L 
and saw-dust or bran. About 19 1-2 pounds of tin are 
required for 300 plates, measuring 1 foot by 9 inches. 
The manufacture of tin-plate in France appears to be 
