78 IMMEDIATE PKINCIPLES OF THE TISSUES. 



It is an interesting fact that in tuberculosis the saponified fats are 

 far more diminished in the blood than in any other fluid. (Becquerel 

 and JRodier.) Solid tubercle itself also contains but little fat ; and 

 it is not an unphilosophical idea that the principal predisposing 

 cause of tuberculosis is this same diminution of fat in the blood, 

 and that it is for this reason that fatty compounds and, above all, 

 cod-liver oil are found so efficient to prevent or arrest it. 



3. Why fat exists in some of the secretions as semen, mucus, 

 &c. is not understood. Of pus, Guterbock found fat sometimes to 

 constitute even 5 per cent.; about 3J per cent, being contained in 

 the corpuscles. But it follows that an excessive secretion of these 

 fluids must produce emaciation, as results from profuse suppuration 

 and from venereal excesses. 



The fat in milk is essential to the development of the young 

 mammal. It constitutes 2J to 4 per cent, of woman's milk, and 

 exists both within cells and in the form of oil-drops. In the colos- 

 trum it forms the peculiar granular cells, or "colostrum-corpuscles;" 

 and which, being also seen in inflammatory exudations, in the sputa 

 of chronic catarrh, in old apoplectic cysts, &c., have been termed 

 "glomeruli" and "inflammation-globules." (Fig. 42.) Not a single 



primordial cell, indeed, can be 

 Flg * 42 ' formed in the embryo without fat 



as one of the elements of its com- 

 position. Hence plastic exuda- 

 tions, also, must always contain 



^ and itg entire absence would 



alone render an exudation non- 

 plastic. In inflammatory exudations, fat is usually more abundant 

 than in the liquor sanguinis. 



4. Fat is present in other tissues than the adipose, in the form of 

 oil-drops, mainly for a mechanical purpose, it would seern ; but 

 when it becomes excessive in amount, a pathological state stearo- 

 sis ensues. 



5. The uses of fat in the food are, in great part, to be directly 

 inferred from the preceding remarks ; but it is also known that fat, 

 in combination with the albuminous elements (albumen, caseine, 

 fibrine, &c.) of our food, renders the latter more easy of digestion. 

 (Lehmann and Elsasser). The presence of fat is also necessary to 

 enable albuminous matters to act as ferments. (Lehmann.) Besides, 

 fat is indispensable for the original development of all the tissues, 



