24 ^ftt)e^et|?amcal©ngtne 



Alkaly-> (I ufed either that of Nitre 

 or of Tartar,) there would be made 

 fo ftrid an.unioo^ that, having^ with- 

 out additaments/liftilled the refitting 

 fait with a ftrong and lafting fire, it 

 appeared not at all confiderably to be 

 wrought upon^ and was not fo much 

 as melted. 



But 'tis not the bare Mixture or 

 Commiftion of Volatile particles 

 with Fixt ones, (yea though the for- 

 mer be predominant in quantity,) 

 that will fuffice to elevate the latter. 

 For, unlefle the figures of the latter 

 be congruous and fitted to faften to 

 the other, the volatile parts will fly 

 away in the Heat^ and leave the reft 

 as fixt as before : as when (and or 

 afhes are wetted or drenched with 

 water, they quickly part with that 

 water, without parting with any de- 

 gree of their Fixity. But on the o- 

 ther fide, it is not always neceffary, 

 that the body^ which is fitted to 

 deftroy^ or much abate, the volati- 

 lity of another fubftance^ (hould be 

 |t felif fixt. For, if there be a skilful 



