1 6 Mayow 



CHAPTER III 



OF THE NATURE OF NITRO-AERIAL AND IGNEOUS 

 SPIRIT 



From what has been already said, it is, I think, to 

 some extent certain what the nature of the nitro-aerial 

 and fiery spirit is. For since the aerial and igneous 

 part of nitre, or what is the same thing, nitro-aerial 

 spirit, exists in the acid spirit of nitre and constitutes 

 its more active part, it follows that the nitro-aerial 

 and fiery spirit is of a^hitro-saline nature, and has the 

 character rather of an acid, than of a fixed, salt. And, 

 assuredly, the effects of fire seem to agree well with an 

 extremely subtle and highly corrosive salt, as will be 

 shown immediately. It must, however, be remarked 

 that this igneous salt is in no way hostile to fixed 

 salts, but, on the contrary, rather intensifies their 

 power than diminishes it as acid liquids do. For 

 fixed salts when heated in the fire become more acrid 

 and caustic in their nature. Certainly the acid spirit 

 of nitre seems to be opposed to fixed salts only as 

 regards its terrestrial and humid part, but not as to 

 its dry and fiery part. Nay, there is not so much 

 contrariety, I think, as is commonly supposed 

 between fixed salt and any acid, as will be more 

 fully expounded below. 



But let us consider in the next place the part which 

 nitro-aerial spirit, or what is the same thing, the 

 aerial part of nitre, plays in producing fire. On this 

 point my opinion is that the form of flame is chiefly 

 due to the nitro-aerial spirit set in motion. For I do not 



