[ i6 ] 
8. Gold leaf melted into the furface of glafs^ by the 
eledhric force, imparts a red colour to it : this 
was firft obferved by Dr. Franklyn, and has 
been often repeated [/]. 
There are many other ways of communicating 
this colour to glafs by Gold ; and I find no method 
by which it can be made to produce any other 
colour. If it be mixed in larger maffes, without 
being minutely divided, it imparts no colour to the 
glafs, but remains in its metallic form. 
Grummet attributes this colour to the manga- 
nefe, ufed in making fome forts of glafs, the colour 
of which he fuppofes revivified by the nitre ufed in 
the preparation of the gold : it is neceflary there- 
fore to mention, that I have given a red by gold 
to feveral glajjesy in the compofition of which 
there was no manganefe, and often by gold in the 
preparation of which there was 7io nitre. 
Several preparations of gold will impart a fine red 
to the fritt or materials of which glafs is made, in 
a fmall degree of heat ; though not minutely 
enough divided, or in too large quantity, to remain 
mixed with the glafs, when expofed to a degree of 
heat fufficient to vitrify them perfectly. 
[/] Franklyn’s Letters on Electricity, p. 65. 
LEAD. 
