34 Mayow 



CHAPTER V 



OF FERMENTATION 



Of Nitro- Aerial Spirit^ so far as fermentations leading to the birth 

 or death of things are caused by it. 



When nitro-aerial spirit effervesces with the saHne- 

 sulphureous particles of the earth in the manner 

 described in the previous chapter, then the nitrous 

 spirit produced by its action meets the fixed salts of 

 the earth, and there is kindled in the earth's bosom that 

 mild and enduring warmth by which the common 

 mother fosters and quickens the seeds hidden in her 

 womb. But that this fermentation may be more 

 clearly understood, let me first speak shortly of the 

 fermentative principles of things. 



Among the elements of natural things nitro-aerial 

 spirit holds the first place, so that it may rightly be 

 called Mercury, since it is a substance exceedingly 

 subtle, agile, and ethereal, and is also the primar}^ 

 instrument of life and motion not only in plants but 

 also in animals, as I shall try to show below. Among 

 the elements of the Peripatetics the two chief are Fire 

 and Air, but for these two our nitro-aerial mercury 

 might justly be substituted, since it possesses a really 

 fiery nature and constitutes also the most active and 

 fermentative part of the air, as will afterwards be 

 shown. With regard to the spirit of the chemists, 

 which usually leads their band of elements, I am quite 

 unable to understand what they mean by the very 

 grand word spirit. For with respect to the spirits of 

 fermented liquids — that is, those which blaze when 



