[ i6o 3 



bad, fee that the maker mend them before yotl 

 take them of him. When you are provided 

 with a plate, the next thing to be confidered iSi, 

 a ground to cover it withal. 



General Inflru5lions in relation to Grounds or Vaf- 

 ni/hes^ proper to lay on the Plates before they arâ 

 etched. 



The ingredients genei-ally made ufe of for the 

 ground or varnifb, are, firft, Afphaltum^ called 

 alfo Pitch of Judea^ox Jew* s Pitch : it is a pretty 

 hard, black, pitchy, or refinous fubftance, com- 

 monly brought to us in large gourd fhells, con- 

 taining, more or lefs, about forty pounds, and 

 to be had of the mofl eminent druggifts in Lon- 

 don. The fécond is Bees-wax, cither white or 

 yellow. The third is common Rofm. The 

 fourth is Maftick, a fort of fine hard rofirl in 

 fmall grains. I have fometimes added a little 

 common pitch to foften it. 



Though it will be proper to vary your ground 

 a little, according to the different times of the 

 year you work in, for that which does very well 



