446 OF NUTRITION. 



shown, takes place in the body at large, as a part of the regular order of 

 things with the advance of years, and also normally occurs in particular 

 organs at earlier periods of life ; but it sometimes takes place prematurely, 

 either in the body at large, or in particular organs, so that they undergo a 

 wasting or degeneration without any ostensible cause. Thus it is not at all 

 uncommon for Articular Cartilages to be almost entirely destroyed through 

 defect of nutrition, without any pain or other symptoms to call attention to 

 the change in progress ;* and many similar cases might be cited. There is 

 reason to believe that "fatty degeneration," the form under which degener- 

 ation most commonly presents itself ( 351), is in reality far more frequent 

 than simple wasting ; but it attracts less notice, because the bulk of the 

 tissue is little or not at all diminished ; and it is only when their function 

 becomes impaired, that attention is seriously drawn to the change. This 

 form of Atrophy can seldom be attributed to antecedent diminution in 

 functional activity ; for it is most common in organs upon which there is 

 the most constant demand for the energetic performance of their respective 

 duties, as, for instance, in the heart, the kidneys, and the liver. But the 

 formative activity of Muscles and Nerves is so closely dependent, as already 

 several times pointed out, upon the active exercise of their functional powers, 

 that atrophy is certain to supervene if this be interrupted ; and this atrophy 

 may or may not present itself under the form of fatty degeneration ; a shrink- 

 age of the parts, concurrently with the production of an increased amount of 

 fat in them, being perhaps the mode in which it most frequently takes place. 

 Atrophy of one part, moreover, may be dependent upon atrophy or imper- 

 fect functional activity of another, if the two be so related in their normal 

 functions, that a decline of one involves a corresponding decline in the other. 

 Thus if a motor nerve be paralyzed, the muscles which it habitually calls 

 into action will be atrophied ; and this will equally happen, whether the want 

 of motive power depend upon a deficient production of it in the nervous 

 centres, or upon an interruption to its conduction through the trunks. 2 On 

 the other hand, if the muscles of a part undergo degeneration from want of 

 use (as in disease of the hip-joint), the nerves which supply them also suffer. 

 The same is the case in regard to the nerves and organs of sense ; for atrophy 

 of the eye will occasion atrophy of the optic nerve, and destruction of the 

 optic ganglia will induce atrophy of the eyes and optic nerves. Even the 

 bones of a limb will suffer, in cases of atrophy of the muscles consequent upon 

 disuse; for in an experiment made by Dr. J. Reid, to determine the effect 

 of artificial exercise in maintaining the nutrition of muscles whose nerves 



1 See Redfern, On Abnormal Nutrition in Articular Cartilages, p. 65. 



2 The Author had some time ago under his observation a case in which three males 

 of a family progressively became affected, between the ages .of 3 and 5 years, with 

 fatty degeneration of the muscles, which proceeded in the most advanced ease to the 

 almost complete obliteration of their normal structure. This change has been con- 

 sidered by many eminent practitioners to be idiopathic ; that is, to have its primary 

 origin in the muscular tissue; and the measures which had been employed to arrest 

 it had been of no avail whatever. It was a strong argument, however, against such 

 a view of the case that, in the Jieart of the eldest son, who died of fever at the age of 

 lii, no fatty degeneration could he discovered ; and on making inquiry into the his- 

 tory of the parents and of their families, ample evidence was discovered for the belief', 

 that the disease was dependent upon the want of functional power in the nervous 

 centres. Acting on this view, it was recommended that the muscular system should 

 be ki'pt as much as possible in a state of active exercise, and that a weak galvanic 

 current should be frequently transmitted through the limbs from the spiue. This 

 treatment proved so far successful that the progress of the disease appeared to be ar- 

 rested, in the most advanced case, whilst a decided improvement took place in the 

 condition of a younger child, who was previously passing rapidly into a state resem- 

 bling that of his elder brothers. 



