90 CONSTITUENTS OF ANIMALS, 



The manner in which Aristotle considered bodies to be 

 made up from the elements may now be- considered. He 

 says that there are three degrees of composition, the first 

 being that out of the so-called elements, such as ai?', earth, 

 water, and fire, or, he says, it would be better to say out of 

 the forces referred to above, the second degree of com- 

 position being that by which the homoeomeria,* such as 

 blood, flesh, bone, stone, and the like, are formed out of the 

 elejnents, and the third being that by which the anhomoe- 

 omeria,t such as the face, hand, and many other parts, are 

 formed out of the homoeomeria. I With respect to the first 

 degree of composition, Aristotle considered that all forms of 

 matter, animate or inanimate, contained some quantity of 

 each of the elements, combined together and not merely in 

 a state of mixture, and that the differences in the properties 

 of these forms of matter, such as differences in heaviness or 

 lightness, roughness or smoothness, were consequential on 

 the proportions of the elements present. § Consequently, each 

 of the substances earth, water, air, and flame, as they are 

 known to us, contain some quantity of each of Aristotle's 

 elements, but earth, water, air, and flame contain preponder- 

 ating proportions of the elements earth, water, air, and fire, 

 respectively. Other forms of matter, even such different 

 substances as stone and palm oil, contain the same elements; 

 their differences are due merely to the different proportions 

 in which these elements are present. The stone contains a 

 preponderant quantity of earth, and the oil contains com- 

 paratively large amounts of air and loater. The oil, if 

 liquid, may be made solid, as is well known, without any 

 change in its chemical composition, but, according to 

 Aristotle's views, the solid oil would differ from the liquid 

 oil chiefly by containing smaller amounts of air and loater. 



Clearly, therefore, Aristotle believed that a change in the 

 relative proportions of the elements in a substance resulted 

 in the production of a substance having properties diff- 

 erent from those of the original substance. This was 

 not all ; it will be evident, from the following account of his 

 views on the constitution of substances, that he held that 

 the elements existed in a state of combination and not mere 



'''- The homoeomeria will be discussed cliiefly in Chapter ix. 

 ■f- The anhomoeomeria will be discussed chiefly in Chapters x.-xii. 

 X p. A. ii. c. 1, 64Ga. 



§ Ihid. ii. c. 1, 646a ; De Gener. et Corr. i. c. 10, 328a, ii. c. 8, 

 3346 and 33oa. 



