FRANCIS BACON 15 



mercury, as it were, pervade the universe; their reasoning about 

 salt, however, is absurd, and merely introduced to compromise earthy 

 dry fixed bodies. In the other two, indeed, one of the most universal 

 species of natural harmony manifests itself. Thus there is a cor- 

 respondence between sulphur, oil, greasy exhalations, flame, and, 

 perhaps, the substance of the stars. On the other hand, there is a 

 like correspondence between mercury, water, aqueous vapor, air, and 

 perhaps pure inter-sidereal ether. Yet do these two quarternions, or 

 great natural tribes (each within its own limits), differ immensely 

 in quantity and density of substance, whilst they generally agree in 

 conformation, as is manifest in many instances. On the other hand, 

 the metals agree in such quantity and density (especially when com- 

 pared with vegetables, etc.), but differ in many respects in confor- 

 mation. Animals and vegetables, in like manner, vary in their almost 

 infinite modes of conformation, but range within very limited degrees 

 of quantity and density of substance. 



The next most general correspondence is that between individual 

 bodies and those which supply them by way of menstruum or support. 

 Inquiry, therefore, must be made as to the climate, soil, and depth at 

 which each metal is generated, and the same of gems, whether pro- 

 duced in rocks or mines, also as to the soil in which particular trees, 

 shrubs, and herbs, mostly grow and, as it were, delight ; and as to the 

 best species of manure, whether dung, chalk, sea sand, or ashes, etc., 

 and their different propriety and advantage according to the variety of 

 soils. So also the grafting and setting of trees and plants (as regards 

 the readiness of grafting one particular species on another) depends 

 very much upon harmony, and it would be amusing to try an ex- 

 periment I have lately heard of, in grafting forest trees (garden trees 

 alone having hitherto been adopted), by which means the leaves and 

 fruit are enlarged, and the trees produce more shade. The specific 

 food of animals again should be observed, as well as that which can- 

 not be used. Thus the carnivorous cannot be fed on herbs, for which 

 reason the order of feidlletans, the experiment having been made, has 

 nearly vanished ; human nature being incapable of supporting their 

 regimen, although the human will has more power over the bodily 

 frame than that of other animals. The different kinds of putre- 

 faction from which animals are generated should be noted. 



The harmony of principal bodies with those subordinate to them 



