28 



Tribune Extras Lecture and Letter Scries. 



has led me to conclude that each half of the- brain 

 paradoxical as ir may seem is a whole brain. That i-, 

 th it one-halt of the bruin Js siillleient for all tin- f unc- 



- ot tin- t\vn halves <f th>- brain, if tiiat n the > 



I must mention a conclusion, although it n> i out- 



(-1 :, ,,r n,, -uriject. It is tliac we are extremely neftlect- 



fill In (-dii'Mting only iino part of the 1m, 1\ . NVe 

 educate OUT ru'i.: arm ami make use of the 

 lixhl Mdr of tin- I M i !y as iniii-!i a> j.os-ible, and leave the 



Li inactive, except In w.iiku.g. Wo do i:t per- 

 furm wbat is really needed if we nav.- two brains. Then- 



question tint it i- iiiir h. ii.it of making uso of only 



tide Of the 1. ."il.V, that consigns to one-half Of the 



lirain th- ri-ht side the fat-nit v <>r expressing Ideas by 

 np.-i di. If we tli % 1. >]i''tl I'oth sides of our body cqua U , 

 i;..t only -would then- be the benefit that \vo could write 

 cr work with n.mdas well as with the right, imt 



we should have two brains instead of one, and would 

 imt in- iii prut- :<>f the power of apeeoli through di> 

 of one .-i.ii- of tin- bi .u:i. 



I pass t.o\\ ID quite another subject. You know that 

 In tl.<- second lecture I said that I would examine two 

 MI H ot facts, oue showing tho power of arrest of 

 activity that nerve force possesses, ami the other having 

 Just the opposite object, tbat la, to produce an activity 

 instead of an urn-sir. I now come, therefore, to tho 

 study of tin- pt-Milnctiim of tho various kind- ot activity 

 tliat tip- iii-ivt- foi-i-c n ."esses. The first question I have 

 to examine is that which relates to theinil jeneo of nerve 

 force in producing muscular contraction! It is essenti.il 

 lir-t io sav a few \vordsou the power of muscular con- 

 traction und to see if th.it power is distinct and 

 independent of iiervo force. There have been 

 a p. ot I many different views about this ; 

 but as I have little time I shall only say that the view 

 is almost universal now that tho nervous system is not 

 esseutial to the existence of muscular contraction or ir- 

 ritability; that contraction can take place without any 

 interiercnce iif t lie nervous system. My friend, Prof. 

 Bernard of Paris made gome luircuious experiments on 

 j'-ct. Ho found that the poison woorari affects 

 tho motor nerves iu muscles, so that tho conductors 

 wliieh unite the brain with tho muscles be- 

 >: paralyzed, while tho muscles remain 

 active. Hi; drew the conclusion that muscles 

 ri in. i in connected with the brain us regards their activ- 

 liy. But there is au objection to this which I put for- 

 ward I -n;.' :i.o. It is not clear at all thac in that case 

 the miiM-ular power in the nV>er is lost. Tue.ro Is a state 

 of tiii HIT-, anatomically and physiologically, insidn of 

 t h i- .-;!i '.it i: ut i he muscular libers, wnicli renders it \ ery 

 doubtful that the wooruri acts upon those parts, ami it 

 limy be i hat I ho nerve power remains inside of tho 

 Mien' i. or the muscular libers. The same objection can 

 be made i- p tin- facts relating to the section ot nerves. 



A MAS : :i:oNGEH WHION I>KAD THAN ALIVE. 



It is \\e.l-lino\vu that If a nerve has been Ulvided, 

 aid r four d..\s it lotji-8 it' power. Tins muscles, how- 

 -. i , i main |H-I f. i-i l.v uetivc, and we can produce eon- 

 tiiiction in them. Unfurl umitcly, here, also, there Is an 

 :; i i.t oi Dem , which Is inside ot tho nerve 



ilh, ami it i> not Known whether It has lost its power 

 Hi l:ot. la 111'- ca^i- i.l I '., o deeiipltalod men, I in.ule a n 

 i\|Hilnient of iiilllnu' oil' the uruirt. I found, after 

 i -i n :ud a liali hum , in 0110 ease and fourteon 

 in the other e.i>-, that all sik'iis of 



lite In the hlnb- had 1 1 1 -a 1 1| -a I etl. Ut) to that 



time, cither t i ivaiii-m or a Khnck produced 

 by a blow Vvitli mv arm or a i)ii])i'r-cntter, 



Hie ijiunciea to i .,-oi,.| tu t he iri ll.itlou. I 



:i-d t he blond of a man into one of thn*o arms, and 

 th.- blond of a iloiT into another. In both cases local lifo 

 was re.-toreil in tin s^ arms. The mii-ieles became irrita- 

 ble ai_ r a;n, and the Mrenirni of contraction was extremely 

 ]io\v. mil. Indeetl. in tin- iiriii in which the blood of tte 

 man had h. en injected, the power was immense. It was 

 greater eei tainiy thiin diirinir life. There was therefore 

 a ret urn uf miiM'iil.ir 11 ritalnlity I'.fter it had disappeared* 

 and nervous c.vitatu'.iiy had not come. Tho nerves 

 remained quite iiead. Tie re fore it seemed quite clear 

 that the muscular irritability depended upon nutrition 

 hv blood and the oxygen in it. The blood injected wad 

 richly charged wall oxvj;-.>:i and ;hat was the reason 

 why the muscular irritation became so creat. There 

 was more oxygen tiian usui.1. As the nerves had not 

 rejaiiied any PO\VI r ar all.it was not through anv influ- 

 ence of tho nerves on the muscles thac the part had 

 re-acquired life. There al>o we tlml, however, that 

 same objection, that we do not know whether tho ele- 

 ments ot tiie nervous tissue which aro inside of tho 

 Mii'.i'h of muscles had lo.^t their power or not. 



But there aro other lact-< more decisive. Professor 

 Simpson of Edinburgh examined the .owerof contrac- 

 tion in the umbilical mrd the cord which unites tho 

 in tus to its mother. In that cord the contraction by 

 .ualvanism was made with great intensity. Some phys- 

 iologists have thought that ther.-are no nervous centers 

 there. If thero are, any, they are very small. In tho 

 iris of au eye I have found a singular fact. Long ago I 

 had discovered thac light can .affect the iris of tho eye, 

 even when it has been removed from the body. Tho eye 

 of tho eel had been removed from the body^for sixteen 

 days and kept at a temperature of about 26 to 40 Fah. 

 But I found that although the eye was in almost com- 

 plete putrefaction, the light still acted as au irritant of 

 muscular fibers. There it was impossible to admit that 

 thero was nervous act ion. The muscular libers them- 

 selves were considerably altered, Still i hey acted. 



But there is a fact which is more decisive to show that 

 muscular irritability is independent of tho nervo'ir sys- 

 tem forits existence. It is that if wo strike a muscla 

 that is dying awav, wo pro luce i ri l_c.: at the place we 

 sirike. All tho libers iu tiie muscle contract at that 

 place. And as it is IMP.. --i .:.- to admit that iu those 

 cases there has been a nervous action in every element- 

 ary fiber, bec;iu.-M- tin- pa -. ; ., 1 snoice of, which aro inside 

 of the sheath, are generally in the mi.ldlo of tho length 

 of the liber, and any part of tho muscle may react in 

 that way, it is, then-lore, imp. .-.-ibh- to admit that there 

 is any nervous action hi Umuo ens -s. Therefore, they 

 show th.it muscles are independent of nerves for their 

 action. 



I pass now to a class of movements which wo call 

 rhythmical. Ic is well known that the heart performs 

 them. Ji has been t|iie..t i.uied \\ln-iner tlie^e move- 

 ments depended on the nervous system. There U no 

 question indeed that in a normal stati I do not say in 

 every Mate tho rhythmical mov -meiits of the he-iri d - 

 peml upon cells of gray mailer \\lin-li ere inside of the 

 lnai t it.scif. The diaphragm, the m.i.-,t important of tho 

 muscles of ii-spira: ion. p < v - IBS, l:Ue i h.- heart, the power 

 n I emit: acting rh> Ilinileally qalie independent of tho 

 brain, the .-pinal cor.:, and t In- inciliiHt utilmiijittii. In 

 almost in I experiments w- Und that when we destroy tho 

 brain or tin <lull<i <ililinti/<itu v,o destroy I ho ir ivement 



also of the diaphragm ; but that Is by the phenomena of 



arrest. \Ve am ft. tho movements of the diaphragm. 



then, a^ we arrest the movements of the heart when wo 



galvanize I no jmr ruiinni. lint if we operate in a certain 

 way v/e m.iy succeed in separating tho diaphragm uou> 



