14 Mayow 



forth call the fiery particles, which occur also in air, 

 nitro-aerial particles or nitro-aerial spirit. 



For, indeed, the spirit of nitre seems to derive its 

 caustic and very potent fiery nature from the nitro- 

 aerial and fiery particles which reside in it. So that 

 it is commonly, and not improperly, called potential 

 fire. And, indeed, when nitre mixed with sulphur is 

 set on fire, it is probable that the nitro-aerial particles 

 of this impetuous flame proceed from the nitrous 

 •spirit, since the fixed salt of nitre, with which the 

 acid spirit is combined, is very alien to the nature of 

 flame, and remains to a large extent at the bottom of 

 the crucible after the nitre has been deflagrated in it. 

 And, indeed, I do not know anything in nature 

 approaching nearer to fire than the red spirit of nitre 

 which passes into the receiver in the course of distilla- 

 tion, with a ruddy colour ; but the ruddiness of nitrous 

 spirit, rivalling flame, seems to be due to the igneo- 

 aerial particles' of the spirit, which are agitated with 

 an almost fiery movement. It is corroborative of this 

 view that the spirit of nitre is extremely corrosive, 

 destructive, and caustic, and possesses a very flame-like 

 nature. And, indeed, it is probable that the form of 

 flame depends largely, if not exclusively, upon nitro- 

 aerial particles such as are contained in the spirit of 

 nitre, as will be shown below. 



One will readily object here that the acid spirit of 

 nitre is by no means combustible, for it will not, like 

 sulphureous matter, blaze if thrown into the fire, but, 

 on the contrary, it will put the fire out. I reply that 

 the igneo-aerial particles existing in the spirit of nitre 

 are in a humid condition, and that they are prevented 

 from beginning a fiery movement on account of being 

 covered over with particles of acid fluid, as we have 

 already intimated. And, indeed, humidity is a very 



