280 NOVUM ORGANUM 



imitated in species, perfected in power, and varied in quan 

 tity; to which should be added the acceleration in point of 

 time. Eust, for instance, is the result of a long process, 

 but crocus martis is obtained immediately; and the same 

 may be observed of natural verdigris and ceruse. Crystal 

 is formed slowly, while glass is blown immediately: stones 

 increase slowly, while bricks are baked immediately, etc. 

 In the meantime (with regard to our present subject) every 

 different species of heat should, with its peculiar effects, be 

 diligently collected and inquired into; that of the heavenly 

 bodies, whether their rays be direct, reflected, or refracted, 

 or condensed by a burning-glass; that of lightning, flame, 

 and ignited charcoal; that of fire of different materials, 

 either open or confined, straitened or overflowing, quali 

 fied by the different forms of the furnaces, excited by the 

 bellows, or quiescent, removed to a greater or less distance, 

 or passing through different media; moist heats, such as 

 the balneum Marice, and -the dunghill; the external and in 

 ternal heat of animals; dry heats, such as the heat of ashes, 

 lime, warm sand; in short, the nature of every kind of heat, 

 and its degrees. 



We should, however, particularly attend to the investi 

 gation and discovery of the effects and operations of heat, 

 when made to approach and retire by degrees, regularly, 

 periodically, and by proper intervals of space and time. 

 For this systematical inequality is in truth the daughter of 

 heaven and mother of generation, nor can any great result 

 be expected from a vehement, precipitate, or desultory heat. 

 For this is not only most evident in vegetables, but in the 

 wombs of animals also there arises a great inequality of 

 heat, from the motion, sleep, food, and passions of the 

 female. The same inequality prevails in those subterrane- 



