364 HISTORY OF 



either by respiration, or by vapours, or by aliment. The 

 first is the best, but, in a sort, out of our power ; the second 

 is potent, but yet ready and at hand; the third is weak 

 and somewhat about. 



40. Air clear and pure, and which hath no fogginess in 

 it before it be received into the lungs, and which is least 

 exposed to the sunbeams, condenseth the spirits best. Such 

 is found either on the tops of dry mountains, or in cham 

 paigns open to the wind, and yet not without some shade. 



41. As for the refrigeration and condensation of the spirits 

 by vapours, the root of this operation we place in nitre, as 

 a creature purposely made and chosen for this end, being 

 thereunto led and persuaded by these arguments. 



42. Nitre is a kind of cool spice ; this is apparent to the 

 sense itself, for it bites the tongue and palate with cold, as 

 spices do with heat, and it is the only thing, as far as we 

 know, that hath this property. 



43. Almost all cold things (which are cold properly and 

 not by accident, as opium is) are poor and jejune of spirit; 

 contrarily, things full of spirit are almost all hot, only nitre 

 is found amongst vegetables, which aboundeth with spirit 

 and yet is cold. As for camphire, which is full of spirit, 

 and yet performeth the actions of cold, it cooleth by acci 

 dent only, as namely, for that by the thinness thereof, 

 without acrimony, it helpeth perspiration in inflammations. 



44. In congealing and freezing of liquors (which is lately 

 grown into use) by laying snow and ice on the outside of 

 the vessel, nitre is also added, and no doubt it exciteth and 

 fortifieth the congelation. It is true, that they use also 

 for this work ordinary baysalt, which doth rather give 

 activity to the coldness of the snow, than cool by itself; 

 but, as I have heard, in the hotter regions, where snow 

 falls not, the congealing is wrought by nitre alone ; but this 

 I cannot certainly affirm. 



45. It is affirmed that gunpowder, which consisteth prin 

 cipally of nitre, being taken in drink doth conduce to valour, 

 and that it is used oftentimes by mariners and soldiers 

 before they begin their battles, as the turks do opium. 



46. Nitre is given with good success in burning agues, 

 and pestilential fevers, to mitigate and bridle their perni 

 cious heats. 



47. It is manifest, that nitre in gunpowder doth mightily 

 abhor the flame, from whence is caused that horrible crack 

 and puffing. 



48. Nitre is found to be, as it were, the spirit of the 



