VARNISHING. 245 



ing glass, and add four ounces of copal, in small 

 pieces ; set it in a sand-heat so regulated, that the 

 bubbles may be counted as they rise from the bot- 

 tom ; and continue the same heat till the solution 

 is completed. 



Camphor acts more powerfully upon copal than 

 any other substance. If copal is finely powdered, 

 and a small quantity of dry camphor rubbed with 

 it in the mortar, the whole becomes in a few 

 minutes a tough coherent mass. The process 

 above described will dissolve more copal than the 

 menstruum will retain when cold. The most 

 economical method will, therefore, be,\to set the 

 vessel which contains the solution by for a few 

 days ; and when it is perfectly settled, pour off 

 the clear varnish, and leave the residuum for a 

 future operation. 



This is a very bright solution of copal : it is an 

 excellent varnish for pictures, and may, perhaps, 

 be found to be an improvement in fine japan 

 works, as the stoves used in drying those articles 

 ,may drive ofi'the camphor entirely, and leave the 

 copal pure and colourless upon the work. 



N. B. Copal will dissolve in spirit of turpentine, 

 by the addition of camphor, with the same facility, 

 but not in the same quantity, as in alkohol. 



A Varnish for Wainscot, Cane Chairs, ^c. 



Dissolve in a quart of spirits of wine, eight 

 ounces of gum sandarach, two ounces of seed-lac, 

 and four ounces of resin ; then add six ounces of 

 Venice turpentine. If the varnish is to produce 

 a red colour, more of the lac and less of sandarach 

 should be used, and a little dragon's blood should 

 be added. This varnish is very strong. 



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