TT7mf Nerves May Do Brown- S^quard. 



81 



foots them by dilating tliom, but because of the direct 

 transformation of nerve force into chemical force pro- 

 ducing mi attraction of blood. A great many facts indeed 

 ehow us that circulation will go on without an impulse 

 from the heart. In plants the circulation proceeds from 

 chemical changes without any heart at all, "without 

 any power that pushes the liquids forward. Tu f octal 

 monsters In our own species, there arc cases in 

 which the monster had no heart, and in which the 

 communication of its circulatory system with that 

 of the almost half child with which it was connected, 

 was too slight for the. circulation to go on if wo were to 

 look upon the heart as the only organ producing circula- 

 tion. Besides, in embryos, in animals at a certain de- 

 gree of their development form the ovum, circulation 

 takes place while the heart is not yet formed. And we may 

 say that instead of the heart beina the only organ that 

 serves for circulation, that, on the contrary, the heart is 

 formed by circulation. The circulation helps to give it 

 a form of organization, and helps to give it a function 

 when it has accomplished its organization. 



I long aco made an experiment with, frogs, consisting 

 In making a section of the ventricle of the heart, 

 dividing it so as to do away with more than 

 two-thirds of the length, of that part. After a 

 time a clot is formed there which unites the 

 lips of the cut, and the circulation goes on with a 

 part of the ventricle, which is so small indeed that there 

 Is hardly an impulse coining from it. There is a pass- 

 age, however, for the blood there, and that is all that is 

 necessary, that the great cause of circulation, which is 

 attraction, may be accomplished in every tissue through 

 life. Even io our own species it has been my lot to see 

 cue rase, that of a lady, in which the heart was almost 

 entirely destroyed by fa:ty deposition. Tlie heart in 

 this case had very little action, if any, but still life per- 

 sisted for some time. In appearance there was a state 

 of health, until suddenly one day death occurred. 

 There is on record the case of a man who for three 

 days had had no beating whatever of the heart 

 nnd who, nevertheless, had had a circulation. 

 He had had no pulse the beating of the 

 pulse depending on the heart but the blood was 

 circulating, and life was maintained all the time. There- 

 fore, although I would not say certainly that the heart 

 is a useless organ [laughter], it is certainly by far less 

 important than it was considered to be, a great deal of 

 the work of circulation being due to the attraction that 

 tissues exert on the blood. That attraetiou is increased 

 by certain nerves, and thereby circulation is consider- 

 ably increased, sometimes locally to a most wonderful 

 extent, by an irritation of the nervous system. In cases 

 of inflammation we see this very plainly. Where the in- 

 flammation exists inside of the cranium, we find that the 

 carotid artery" beats with trcmeudous violence. Some- 

 times we flud an enormous increase of pulsation in the 

 arteries of the temple. As we flud ip such cases that 

 the heart, as indicated by the pulse In the wrist, is not 

 beating with much more force than usual, we must con- 

 clude that there is considerable irritation and an in- 

 flammation in the membrane of the brain or the brain 

 Itself. 



A CAT'S TAIL ON A ROOSTER. 



If we put an organ taken from a living animal inside of 

 another animal, very frequently this organ will bo en- 

 grafted there. The infused serum becomes the object of 

 chemical change?, the blood is attracted and the organ 

 receives circulation. I once engrafted the tail of a cat 

 on -A cock's comb. A few days after it was evident by 

 pnckiug fhe tail that blood waa circulating in it, aud it 



certainly would ha :o stayed them had not the cock had a 

 light and lost its tail. iLaiighter.J Other cases of graft- 

 ing leave no doubt in this respect. It Is shown by the 

 fact that ova in animals when they nre implanted on a 

 mucuous membrane take hold of it, blood is attracted 

 there and circulation takes place. 



Now, the question is, does the nervous system which 

 acts so powerfully on nutrition, as you will see In a 

 moment, act only through blood vessels and through 

 lhat peculiar influence which I had named an attraction 

 of blood 1 Certainly not. Whatever bo the suppositions 

 we may make as regards the mechanism by which tho 

 alterations I will speak of arcproduced.it is quite cer- 

 tain that we cannot explain all the facts on the suppo- 

 sition that the nervous system affects nutrition only 

 through tho blood vessels. There must be other influ- 

 ences. And the variety of facts I shall mention, 

 although not so great as I should like to present, will 

 be sufficient, I think, to show that we cunnot accept that 

 position. 



The, mere division of a nerve is followed by a good 

 many alterations, often producing atrophy not only of 

 the muscles but also of the cellular tissue of the blood 

 vessels, and also of the bones themselves. All the parts 

 that wore animated by the nerve are more or less atro- 

 phied after division. Dr. John Bead made an experi- 

 ment to ascertain whether it was because the nervous 

 s.vstem has an influence on tho nutrition, which is essen- 

 tial, or whether it was simply the lack of action, the 

 perfect rest in which the part was thrown, that occa- 

 sioned this wasting away or atrophy. He allowed 

 atrophy to take place, and then galvanized the limb 

 very frequently, aud found it improved. But the prin- 

 cipal experiment consisted in preventing atrophy by 

 galvanization. He galvanized every day, and found 

 that the limb did not become atrophied. I pushed the 

 experiment further. I waited until atrophy had be- 

 come considerable in the limb, and then I applied gal- 

 vanism. I then learned that although tha nerve had 

 lost uerve force altogether as they lose it four days 

 after dissection yet there was soon a manifest in- 

 crease iu size, and after a time the limb was brought to 

 the normal size that it had before the operation. 



Even in man we frequently see cases of that kind. I 

 once had a patient who from rheumatism had been 

 without any exercise in one of his legs for a long time 

 aud atrop'jy was considerable in the thigh. When the 

 pain had diminished considerably he began to apply gal- 

 vanism. I observed day after day a change for the bet- 

 ter, and at the end of a week he had gained at the upper 

 part of tho thigh five centimeters. or nearly two inches 

 in circumference. This implied a rapid transformation 

 for the better. Ic is evident, therefore, that in a great 

 measure it is owing to rest or inactivity of a pnrt that 

 want of nerve action and consequently atrophy is due.. 



CONSEQUENCE3 OF IRRITATION TO NERVES. 



There is a great variety of results, as 1 have said, when 

 any part of the nervou s.vstem is irritated. The irrita- 

 tion may come in a direct way ; that is, it may, if it 

 exist in the brain or part of the spinal cord, go direct to 

 the muscles or skin or bones or glands or part with 

 which it is connected. But there is another way. An 

 irritation may start from a part of the skin or mucous 

 mombrauco and go up to the brain or spinal cord and be 

 sent back by the brain or spinal cord toward other 

 organs which become atrophied. There are a number 

 of cases which show that an irritation in tho bowels or 

 elsewhere, in the skin, for instance, from a cut, haa 

 produced an atrophy at a distance in other parts of the 

 body. Tho variety of effect produced is considerable. 



