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waR decapitated and dividcd just below tlie third vertebra. The eves 

 continued dravvn in, and no motion could be detected on irritating 

 the eye, eyelid, or skin. But both ihe anterior and posterior parts 

 reniained tetanic as before. The limbs \verc moved in the šame spas- 

 modic manner by the šame slight impressions. The exalted conditioii 

 ot the function of thesentient and motor nerves continued in each 

 part. AU was changed on removing the brain and the respective 

 portions of spmal manow. The eyes were immovable, but no longer 

 retracted ; the museles of the limbs were flaccid, and there was no 

 evidence of uritability in the sentient nerves. 



" These experiments," Dr. Hali continued, " appear to me to 

 estabhsh a property or function of the nervous system,—of thesentient 

 and motor nerves,— distinct from sensation and voluntarv or instinc- 

 tive motion. Hovvever doubtful this conclusion might a'ppear in re- 

 ference to the first series of experiments upon the animal in its natūrai 

 State, lt can scarcely admit of doubt vvhen we compare \vith them the 

 phaenomena observed in the frog made tetanic bv opium. In this case 

 the contraction oflhe museles is plainly no< the result of volition ; and 

 lt obeys the šame lavvs, in regard to i'ts continuance and extinction, 

 as the simdar function or property in its natnral and unexalted statė. 

 Neither does it arise from the irritation of the motor nerves, or mus- 

 cular fibre ; for it ceases on removing the spinal manovv, whi]e the 

 property ofirritability continues unimpaired after the destruction of 

 the nervous centre. I conclude, then, that there is a property of the 

 sentient and motory system of nerves which is independent of sensation 

 and volition ;-a property of the motor nerves independent of imme- 

 diate irntation:— a property vvhich attaches itself to any part of an 

 animal, the corresponding portion of the brain and spinal marrovv of 

 which is entire. This property is capable of exaItation, in the frog, 

 from the inflnenceof opium, and doubtless of strychnine ; and I mav 

 add, that it is diminished or extinguished by the hydrocyanic acid. It 

 is naturally greatest in animals of lovvest senšibilitu, as the cold- 

 blooded." 



With regard to the office performed bythis propeity of the nervous 

 system in the animal oeconomy, Dr. Hali stated that it appeared espe- 

 cially to preside over all those functions which, from appearino- 

 neither exclusively voluntary nor independent of the vvill, have been 

 designated mixe(l. That the function of respiration is of this kind he 

 considered plain from the phaenomena presentedby the sepaiated head 

 of the turtle, in which the submaxil!arv integuments became alter- 

 nately inflated and contracted as in ordinaiy respiration. The ac- 

 tions of coughing, sneezing, vomiting, &c. are of the šame kind. 

 So apparently is the siugnlar effect producrd by tickling. Of all the* 

 parts of the human frame the laryni- and the anus appear to be most 

 under the influence of this peculiar po\ver. No part is so impatient 

 of irritation as the former ; none so much in need of automatic 

 action as the latter, vvith the other sphincters. These very parts are 

 subject moreover to peculiar morbid aflFections of this function : in 

 regard to the (an/Hx it is observed in some affections of dangerous 

 tendency referred to spasm : in the sphincters it is seen in those sin. 



