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glafs and handle but pitch ; you then lay down the 
glafs and handle upon fomething flat, taking care 
that the handle is in the middle of the glafs, till it is 
entirely cold. It is very material to know, that the 
pitch, to be ufed for faftening the handle to the glafs, 
mufl; be foft pitch, that has never been ufed, nor 
melted j for any other pitch will infallibly bend the 
glafs. 
You then grind your glafs in the concave tool 
with emery, and give it the proper figure and 
fmoothing for the lafl; polifli, in the common manner. 
In order to give your glafs the lafl: polifli, which is 
the mofl; difficult part of the whole work, you are to 
prepare fome pitch for covering the before mentioned 
polifhing concave tool, which is done in this manner : 
Take fome pitch, and melt it in an iron ladle, and let 
it boil for a quarter of an hour or thereabouts ; by 
this boiling, the pitch, when cold, will become hard 
and brittle j or you may fliorten this operation, by 
melting equal quantities of pitch and rofin, and then 
there is no occafion to let it boil fo long. Your pitch 
bein'y thus prepared, you again melt it, and take it 
off the fire, and let it fland till the pitch becomes 
pretty cold, or of a tbickifli confiftence ; and having 
warmed the polifhing tool a little, to make the pitch 
flick to it, you pour out of the ladle upon the po- 
lifliin^T tool as much of the pitch as you judge will 
cover^the whole tool, when fpread out, to about the 
thicknefs of of an inch ; you then invert this tool 
with the pitch upon it, and prefs it upon the convex 
tool, which mufl be quite dry, clean, and cold, m 
order to give it the figure of the convex tool ; m cafe 
it has not fpread out fo as to cover tlie whole furface 
