212 THE PHILOSOPHY 



The chyle, as formerly remarked, is converted into blood. The 

 glutinous part of the blood, known by the name of coagiilable lymph, 

 refembles the white of an egg. That the white of an egg is the fole 

 nourifliment of the chick before its exclufion, is an eftabliflied fa£t; 

 and the conclufion, from analogy, that the lymph of blood is deftin- 

 ed for the growth and reparation of animal bodies, is by no means 

 unnatural. * Without repeating,' fays Dr Monro, ' our extreme 

 uncertainty as to the tubular nature of the nerves, and the impro- 

 bability that canals fo exceedingly minute as thofe within the 

 nerves mufl be, and of fuch length, are deftined for the convey- 

 ance of glue, do we not find, that this very matter is feparated by 

 the exhalant branches of the arteries of the peritoneum, pleurae, 

 and other fhut facs, and univerfally, by the branches of the ar- 

 teries of the cellular membrane ? — The kinds of matter neceffary 

 for the growth and nourifhment of our feveral organs are fo vari- 

 ous and different in their nature, that it is altogether incredible they 

 can be furnifhed by the nerves : Thus, water is needed for the ex- 

 tenfion of the fore-part of the eye, vifcid matter for the cryftalline 

 and vitreous humours, earth for the growth of the bones, &c. ; 

 whereas we can as cafily conceive thefe to be furnilhed by the ar- 

 teries, as that, in one place, they (hould furnifti faliva, in another 

 b||€, &c. — As the wafte of the feveral organs is carried off by the 

 veflels, either circulating or abforbent, why fhould we doubt that 

 the circulating fluids can add a particle in the place of one that has 

 been carried off, or that an artery can fupply what has been abforb- 

 ed by a lymphatic vein ? As it is granted that the fecretion of all 

 other kinds of matter in the bodies of animals is performed by the 

 branches of the arteries, is it not incredible that there fhould be 

 an exception to the general rule in the fecretion of the nourifh- 

 ment ? Surely that power which can convert the food into blood, 

 and can change the blood into bile and faliva, is fufficient to con- 

 vert it into nourifhment. 



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