ADIPOSE TISSUE. 



61 



Thus it is less oleaginous, and more brittle 

 and friable than true fat. In the infant this 

 layer continues the same in quantity, but a little 

 more oleaginous, till the period at which the 

 individual begins to exert the muscles of loco- 

 motion. The fat then rapidly diminishes in 

 quantity, and after the child has begun to 

 walk and run, the fat has almost entirely dis- 

 appeared from most parts of the adipose tissue, 

 except the orbits, cheeks, neck, buttocks and 

 the flexures of the joints ; but even in these 

 regions it is much less abundant and much 

 more consistent. 



The marrow presents similar changes. The 

 bones of the foetus are void of a distinct me- 

 dullary canal, and present merely a reddish, 

 homogeneous, vascular pulp, some\vhat con- 

 sistent, but presenting soft compressible por- 

 tions. This state continues some time after 

 birth. As the individual passes from infancy 

 to childhood, the interior of the bone is formed 

 into cancelli, adipose or oleaginous matter is 

 deposited in the intra-osseous tissue within 

 the cancelli, and as the vessels of the medullary 

 membrane gradually mould the medullary 

 canal, this oleaginous matter is most abun- 

 dantly deposited in the interior of the cylin- 

 drical bones. The marrow, however, is much 

 less oleaginous, and more like a pulpy paste 

 than it is in the adult. 



During the periods of boyhood and youth 

 fat continues very sparing in the adipose tissue, 

 and especially in the male sex. After puberty, 

 however, it becomes more abundant, especially 

 in females. After this period the deposition 

 of fat depends more or less on the habits of 

 the individual, as to eating and drinking and 

 corporeal exertion. In general the deposition 

 of fat becomes more copious and general after 

 the age of forty or forty-two than previously. 



From these several facts it appears to result 

 that fat is to be regarded as a secretion by the 

 capillary vessels of the adipose tissue from the 

 blood, and that the tissue and its vessels are 

 to be distinguished from the fat or the matter 

 secreted in the relation of vital agents and 

 organic products. Upon the whole the idea 

 of Haller as modified by Mascagni regarding 

 the origin of the fat appears to be the most 

 probable, viz. that, while the arteries secrete 

 an imperfectly formed oily fluid, the thinner 

 parts are absorbed either by lymphatics or by 

 veins, and the residue is left in a more con- 

 sistent and solid form. 



I think, in conclusion, that, taking all the 

 circumstances already stated into consideration, 

 it may be inferred that adipose matter, or its 

 constituent elements exist in the blood, chiefly 

 as complementary elements of the albuminous, 

 gelatinous, osmazomatous, or gelatino-albu- 

 minous principles employed in the nutrition of 

 the several tissues ; and that, as the carbon, 

 hydrogen, oxygen, and azote are employed in 

 the formation of the latter tissues, the great 

 excess of carbon, and the smaller excess of hy- 

 drogen and oxygen, not employed in the for- 

 mation of these tissues are arranged by the 

 capillaries in such proportions as to form adi- 

 pose matter; and that this adipose matter, 



though fluid, when first formed, becomes more 

 consistent and fixed after deposition in its 

 appropriate tissues. 



The pathological conditions of the ad i pom: 

 tissue. 



\. Inflammation. From various facts, and 

 especially, observing the phenomena of certain 

 cases of what have been denominated diffuse 

 inflammation of the cellular membrane, 1 for- 

 merly inferred that the peculiar phenomena of 

 certain intense and malignant forms of this 

 disorder, depend on inflammation not of the 

 cellular membrane, but of the adipose tissue. 

 This conjecture I have since had opportunities 

 of completely verifying as to certain, if not the 

 majority of cases of diffuse inflammation. 



a. In cases of diffuse inflammation affecting 

 the arm, the inflammation has spread along 

 the adipose membrane, producing sero-puru- 

 lent suppuration and sloughs of the adipose 

 tissue. In cases of inflammation at the verge 

 of the anus, the disease spreads along in the 

 same manner, and affects, almost exclusively, 

 the adipose tissue around the anus and rectum, 

 and along the gluttei muscles. It is in the 

 same manner that the adipose cushion, with 

 which the bloodvessels are surrounded, is oc- 

 casionally the seat of a species of bad inflam- 

 matory action terminating in fetid and sloughy 

 suppuration. 



That these forms of diffuse inflammation 

 truly depend on inflammation of the adipose 

 membrane, I must further maintain, from the 

 fact that the disease occurs not only in the ex- 

 ternal adipose cushion, but in the internal or 

 sebaceous fat. I have seen an example of in- 

 flammation in the adipose cushion surrounding 

 the left kidney, in which the whole of this 

 substance was converted into an ash-coloured, 

 fetid, semifluid pulp, mixed with shreddy fila- 

 ments, and in which this suppurative slough- 

 ing process had opened a passage from the fat 

 of the left kidney into the interior of the trans- 

 verse arch of the colon. The instance of in- 

 flammation and subsequent mortification of the 

 adipose membrane surrounding both kidneys, 

 detailed by Dr. Thomas Turner, in the fourth 

 volume of the Transactions of the College of 

 Physicians in London, is an example of the same 

 species of disease. In the case witnessed by my- 

 self, the disease gave rise to the usual symptoms 

 said to attend diffuse inflammation. Though 

 no great degree of pain was felt, the pulse was 

 quick and small, the tongue brown and dry, 

 the countenance dingy and lurid, and the eyes 

 heavy, the bowels difficult to be affected by 

 medicine, the urine scanty and high-coloured, 

 and at length suppressed ; and the patient, 

 after muttering delirium and typhomania on the 

 second day of the attack, with subsultus tendi- 

 num, passed into a comatose state, which ter- 

 minated on the fourth day in death. 



h. This doctrine further does not rest upon 

 evidence deduced from the mere symptomatic 

 characters of the disorder. In fatal instances 

 of diffuse inflammation, we find the adipose 

 membrane not only partially mortified and 

 suppurated, but that part of it adjoining to the 

 skin and to the bloodvessels very much loaded, 



