RESEMBLANCES AND DIFFERENCES. CCXCV 



observe if there is not some instance which marks the cause 

 of the sought nature. Let the nature sought be gravity. 

 Heavy bodies, having a tendency to the earth, must fall ex 

 mero motu, from their own construction, or be attracted by 

 the earth. Let two equal bodies fall through equal spaces 

 at different distances from the earth, and if they fall 

 through these equal spaces in unequal times, the descent 

 is influenced by the attraction of the earth. 



4. RESEMBLANCES AND DIFFERENCES. 



Observe resemblances between apparent differences. 

 Are not gums of trees and gems produced in the same 

 manner, both of them being only exudations and percola 

 tions of juices: gums being the transuded juices of trees, 

 and gems of stones ; whence the clearness and transparency 

 of them both are produced by means of a curious and 

 exquisite percolation? Are not the hairs of beasts and 

 the feathers of birds produced in the same manner, by 

 the percolation of juices? and are not the colours of 

 feathers more beautiful and vivid, because the juices are 

 more subtilely strained through the substance of the quill 

 in birds than through the skins of beasts? (a) Do not 

 the celestial bodies move in their orbits by the same laws 

 which govern the motions of bodies terrestrial (6) 



From the conformity between a speculum and the eye, 

 the structure of the ear and of the cavernous places that 



() Does not an apple fall from a tree, and do not the planets move 

 in their orbits by the same laws ? 



(6) See De Aug. L. iii. p. 169. &quot; Quicunque enim superlunarium et 

 sublunarium conficta divortia contempserit, et materiae appetitus et pas- 

 siones maxime catholicas (quae in utroque globo validae sunt, et universi- 

 tatem rerum transverberant) bene perspexerit, is ex illis quae apud nos 

 cernuntur luculentam capiet de rebus coelestibus informationem, et ab iis 

 e contra quae in coelo fiunt hand pauca de motibus inferioribus qui nunc 

 latent perdiscet; non tantum quatenus hi ab illis regantur, sed quatenus 

 habeant passiones communes.&quot; 



