SECTION IIL 75 



When the Shells are pohflied enough, 

 and quite dry, pafs them over by a fine pen- 

 cil with gum arable water; which glows 

 the colours without hurting them, or even 

 giving any fmell, as varnifh does. Whites 

 of eggs is alfo good ; it is more glaring, 

 but, however, it is fubjedl to turn yellow 

 in time. 



The lafl: and leaft work to be u fed for 

 Shells, is working or rubbing them quite 

 down, fo as to take off entirely their true 

 and native coat. This is done by working 

 them like agates, or other ftones, on wheels 

 fmeared with emery. This work often 

 guite fpoils them, and very great care 

 muft be taken : however, they may be 

 poliflied by hard bruflies of boars briftles, 

 with a turning machine. 



Patience and judgment can only over- 

 come working of Shells that are warped, 

 rugged, bumped, thorny, &c. A brufh or 

 a feather can only be ufed to convey the 

 4 aqua 



