SEARCH
0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Prev | Current Page 246 | Next

Babbage, Charles, 1792-1871

"On the Economy of Machinery and Manufactures"


233. 6. Tinning. The pins are now fit to be tinned, a process
which is usually executed by a man, assisted by his wife, or by a
lad. The quantity of pins operated upon at this stage is usually
fifty-six pounds. (a) They are first placed in a pickle, in order
to remove any grease or dirt from their surface, and also to
render them rough, which facilitates the adherence of the tin
with which they are to be covered. (b) They are then placed in a
boiler full of a solution of tartar in water, in which they are
mixed with a quantity of tin in small grains. In this they are
generally kept boiling for about two hours and a half, and are
then removed into a tub of water into which some bran has been
thrown, for the purpose of washing off the acid liquor. (c) They
are then taken out, and, being placed in wooden trays, are well
shaken in dry bran: this removes any water adhering to them; and
by giving the wooden tray a peculiar kind of motion, the pins are
thrown up, and the bran gradually flies off, and leaves them
behind in the tray. The man who pickles and tins the pins usually
gets one penny per pound for the work, and employs himself,
during the boiling of one batch of pins, in drying those
previously tinned.


Pages:
234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258