Notes, ii. 4 — 5. 1 63 



• fibrine is a higher elaboration of the albumen of the serum, necessary before this can 

 be put to use ; and with the undoubted fact that the blood is not only the channel for 

 nutrimMit, but also the channel by which such waste as arises from decay is carried off 

 to the excretory organs. That "the necessary process" means the waste of the body 

 caused by its own activity is shown by De Soiiino (3, 10) : " Toil produces wasting ; and 

 the product of this waste, unless it be cold, is similar to unconcoGted nutriment." 



(Ch. 6.) 1. A. calls the softeir kinds of fat Lard, the harder kinds Suet. This 

 answers to the division .of later writers into Pinguedo and Sevum. J. Hunter made four 

 divisions. Oil, Lard, Tallow, Spermaceti, also taking consistency as the basis of 

 distinction. 



2. We have here an example of the manner in which the ancient philosophers judged 

 of the composition of a substance. They simply inferred it from a comparison of the 

 superficial qualities with those of the four elements. Oil is shining; so is fire. Oil 

 is more or less transparent ; so is air. Oil then contains fire and air. There was no 

 attempt to reduce bodies to their supposed constituents by actual analysis. " The 

 supposed analysis was, in short," says Whewell, "a decomposition of the b.ody into 

 adjectives not into substances." 



3. This is an error, ,'ln caterpillars, for instance, there is abundance of fat, ^ A. 

 himself later on (iv. 5, 30) speaks of the Echini as having something like fat, mistaking 

 the nature of their ovaries. He would say, however, that these substances are not true 

 fat, but ortly something analogous to fat (Z>, G. i. 19, 18), just as he says that the 

 ex-sanguineous animals have no true blood, but only something analogous to blood. 



4. The coagulation of broth, is due to gelatine and not to fibrine. These substances, 

 however, were of course not distinguished by Aristotle. This may perhaps account in 

 part for his supposing that the fluidity of the- blood was due to heat, and its coagula- 

 tion, when withdrawn fronT the body, to cold ; for gelatine is thus affected by heat and 

 cold. 



. 5, Cf. iv. 16, Note 44. ■ , . 



6. The fat of Ruminants and Rodents is harder than that of man ; the fat of 

 Carnivora and Pachyderms softer. A.'s statement is therefore correct, excepting, as 

 regards the Rodents, which he did not distinguish from the Carnivora. Though he . 

 makes no mention of Pachyderms in this place, elsewhere {,H. A. iii. 17, i) he correctly 

 says that the horse and the hog have soft fat. 



7. Gf. ii. 3, Note 15 ; ii. 10, Note 10. ^ 



8. Cf. Thackrah, " On the Blood" p. 131 : " The state of the general system as to 

 Fatness or Leanness seems to affect the quantity and character of the blood. Fat 

 animals have I believe considerably less blood in proportion to their weight . than lean 

 ones ; and in the fat human subject venesection shows the veins to be comparatively small, 

 and the quantity of blood, even when two Dr three vessels are opened, is less than flows 

 from one vein of a lean person, etc." So also Ijippocrates {Aph. i. 44) : "Those who are 

 naturally very fat are likely to die earlier than those who are. slender ;" which Galen 

 explains by saying that fat men have smaller vessels than lean ones, and so are less 

 plentifully supplied with vital spirit (irj/cC/ia). Cf. Celsus, ii. l ; Hippocr. Kukri's ed. 

 iii- 434- 



9. Cf. D. G. i. i8, 59. That over-fat animals are bad breeders is known to every farmer. 

 So tilso it is well known that castrated animals grow fat. These and similar facts led 

 Bichat {Anat. Gen. i. 55) to express an opinion much the same as that 'of Aristotle. 

 " On dirait qu'il y a un rapport constant et rigoureux entre la secretion de la semence et 

 I'exhalation de la graisse ; que ces deux fluides son! en raison inverse I'un de I'autre." 



