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COPAL AND COPAL VARNISH. 
COPAL AND COPAL VARNISH. 
On the different sorts of Copal found in the market, and on the Mode of 
Manufacturing Copal Varnish for certain purposes. 
By M. R. Schindler. 
There are three sorts of copal to be found in the market, with- 
out either of them having any other name attached, whereby to as- 
certain this difference, than the terms East and West India copal, 
the latter term including two kinds very different from each other. 
As to the East India copal, called also African copal, it is softer, 
more colorless, and transparent than the other varieties, always 
having a clean surface, and emitting an agreeable odor when 
heated. Its form is globular, and it would be as well at once to 
give it the name of globular copal, as a distinctive mark. This is 
the copal which furnishes the best varnish. Old oil of turpentine 
has but little action on this copal ; more recently-distilled turpen- 
tine dissolves it completely ; but not in a larger proportion than 
its own weight, or the excess of copal is precipitated, Rectified 
turpentine, or turpentine digested with sulphur, is able to take up 
double its weight of this copal without any precipitation — the so- 
lution, however, at this strength, is somewhat turbid. 
Oil of rosemary, thick and old, only causes the copal to swell ; 
that which has been newly rectified, or as it is usually met with in 
the market, provided that it has been carefully kept, dissolves the 
copal in any proportion giving a clear yellowish solution 5 which, 
in the proportion of equal parts of oil and copal, remains fluid 
enough for use. 
This kind of copal fuses much more readily than the other two. 
It is less volatile, and gives out no empyreumaticoil, but only some 
watery acid. If the operation be performed without access of air, 
fire carefully regulated, and the vessels so constructed as to allow 
the free disengagement of the liquid substances formed, this copal 
is not darker after than before fusion. As soon as it ceases to froth 
up, the fusion is complete, and then good oil of turpentine dissolves 
the copal in any proportion, and forms, according to the solvent 
used, a beautiful and good varnish for the metals, paintings, wood 
exposed to air, leather, &c, &c. 
The second kind of copal, called West India copal, or American 
