8 OP THE BLOOD. 



most probably to be ascribed to the oxide of iron,* the 

 quantity of which, however, is so minute, that it has 

 been most variously estimated. (F) 



14. The last constituent principle of the blood to be 

 noticed, is the plastic lymph, formerly confounded with 

 the serum. This has been called the basis of the cras- 

 samentum, the glutinous part, the fibre or fibrous matter 

 of the blood, and, like the caseous part of milk and the 

 gluten of vegetables, been discovered by late anal \ sis 

 to abound in carbon and azote. (G) 



15. It is properly denominated plastic, because it 

 affords the chief materials from which the similar 

 parts, especially the muscles, are immediately pro- 

 duced; nourishes the body throughout life; repairs 

 wounds and fractures in an extraordinary manner ; fills 

 up the area? of large blood vessels when divided ; and 

 forms those concretions which accompany inflamma- 

 tions^ and that remarkable deciduous membrane found 

 in the recently impregnated uterus for the attachment 

 of the ovum. 



16. Thus much have we said, respecting the consti- 

 tuent parts and nature of the blood, the most important 

 fluid of the animal machine, — a fluid, which excites the 

 heart to contraction ; which distributes oxygen to every 

 part, and conveys the carbon to the excretory vessels, 

 giving rise, by this change, to animal heat ; which sup- 



* By Will. C. Wells, Philos. Trans. 179", the redness of the blood in general 

 is rather ascribed to the peculiar structure of the globules, and its various 

 degrees and changes simply to the reflection of. light. 



f Such are those spurious membranes found exuded on the surface of in- 

 flamed viscera, v. c. those cellular connections between the lungs and pleura 

 after peripneumony, and the tubes observed within the bronchia; after croup : 

 such also arc those artificial ones called, after their inventor, Ruyschian, and 

 made by stirring fresh blood about with a stick. 



