USES OF THE FIBRIN. 711 



though often beneficial, sometimes induces injurious consequences to 

 the system, as, for example, in adhesive inflammation of the perito- 

 neum, by which the intestines and other organs become adherent, or 

 constricted by bands of newly-formed tissue, which interfere with, or 

 altogether hinder, their proper movements and actions ; in similar adhe- 

 sions between the lungs and the side of the chest, between the heart 

 and the pericardium, and also, and still more strikingly, in the attach- 

 ment of the iris to the capsule of the lens, or other parts within the 

 eyeball, even causing blindness by the complete closure of the pupil. 

 Not only fibrinous exudations from the vessels, but even extravasated 

 blood itself, may coagulate within the tissues; by some, it is maintained 

 that it may itself become the seat of subsequent organization. 



The fatty matter of the blood, which is of various kinds, is highly 

 nutritive, scarcely any tissue being altogether destitute of fat in larger 

 or smaller quantity. Phosphorized fats especially abound in the ner- 

 vous substance, and exist in the red corpuscles of the blood. Fat is 

 always present in newly-forming tissues and newly-forming cells, the 

 nuclei of which often contain fatty particles surrounded by an albumi- 

 nous deposit. Fatty matter is found, too, not only in the fluid parts 

 of the blood, but also in the organized morphological elements, the 

 blood corpuscles, especially in the red ones. It was observed by 

 Ascherson, that when oleaginous substances are agitated with albumi- 

 nous solutions, the fatty matter breaks up into minute particles, sur- 

 rounded by a film of albumen ; and he believed that some such physical 

 combination of oleaginous and albuminous matter, might explain the 

 formation of the lowest morphological elements, such as granules, and 

 even of certain nuclei, though not the origin and growth of cells them- 

 selves. Without adopting this view, it may be admitted that fatty 

 matter is essential to all nuclear and cell growth, and to every pro- 

 cess of tissue formation, even to the assimilation of albuminous matter; 

 for fat-globules are always present in the ovum or germ-cell of every 

 animal. Fat is necessary to the formation of certain secretions, as of 

 the bile, milk, and sebaceous matters of the skin. The bile contains 

 a very large quantity of fatty acids. It is possible that fat itself may 

 be derived from other constituents, as from albuminoid, amyloid, or 

 saccharine matter. The great value of oleoids, especially of such as 

 are easily digested, absorbed, and assimilated, is .exemplified in the 

 beneficial action of cod-liver oil in tuberculous diseases. Besides its 

 use as a nutritive substance, the fat of the blood is probably also con- 

 stantly subject to oxidation, for the production of animal energy and 

 heat. But there are other substances in the blood, which ar'e proba- 

 bly even more easily oxidated than its fats. 



Arterial blood does not contain any amyloid substance ; but traces 

 of sugar are present in it. This is formed in the liver, but also, it 

 would seem, in the muscles, and probably in other parts; it is also 

 taken up from the food. Nevertheless, the quantity present is small; 

 it is, perhaps, less concerned in nutrition than in the production of heat 

 and motion by its rapid oxidation. It may, however, take part in the 

 formation of milk. The inosite, lactic acid, creatin, and creatinin, 

 and other extractives, are probably not so much directly nutritive, as 



