i4 8)t tfre 9ecf»anlcal 3D psfnt of 



Wax being thereby removed from 

 the ftrokes made by the (harp bo-' 

 dy, 'tis eafie to etch with Sublimates 

 fince you need but ftrew the pow- 

 der of it upon the place bared of 

 the Wax, and wet it well with, 

 meer common water > for ftrong 

 Vinegar is not neceffary. For after 

 a while all the parts of the blade 

 that fhould not be fretted , being 

 prote&ed by the Cafe or Film of 

 Wax, the Sublimate will corrode 

 onely where way has been made 

 for it by the bodkin , and the Let- 

 ters will be more or lefs deeply in* 

 graven ( or rather etch'd ) accord- 

 ing to the time the Sublimate k fuf- 

 fer'd to lye on. And if you aim 

 onely at a legible im predion., a few 

 minutes of an hour (as four or five) 

 may fcrve the turn. 



EX- 



