262 DICTIONARY OF THE VETERINARY ART. 



does through metallic wires ; others suppose that the motion 

 is that of electricity itself. My own opinion is, that it is 

 based on the principle of elasticity. It is well known that, 

 if any number of ivory balls be suspended in contact, and in 

 a direct horizontal line, and a blow be struck on the first in 

 the direction of all the rest, all remain at rest except so many 

 at the other end as exactly equal the momentum of the blow. 

 These fly off from the rest. If the blow be equal to one 

 ball, only one ball flies off. Now it would be the same if the 

 balls were confined in a tube, were the tube ever so crooked, 

 as is proved by the hydrostatic balance of fluids in crooked 

 water-pipes. I believe that the nerves are sheaths filled with 

 extremely elastic globules of matter, and the impressions, or 

 momenta, communicated to one end are transferred to the 

 other, not by the locomotion of the whole globule, but by 

 the elastic spring of its centre. If the impression be made on 

 any of the intermediate globules, the result is the same. It 

 is remarkable that in whatever part of a nerve the impression 

 is made, the effect produced is referred to the extremity." 

 (See Distribution of Nerves, part first.) 



Nerving, Nerve Operation. It consists of cutting out a 

 portion of the nerve which supplies the foot, either just above 

 the fetlock joint, which is named the high operation, or in 

 the pastern, which is called the low operation. In the former 

 the sensibility of the foot is supposed to be entirely destroyed, 

 and in the latter only partly so. Dr. White observes, serious 

 mischief, such as the loss of the hoof, has sometimes followed 

 the higher nerve operation. 



" After the division of a nerve, the extremities of the divid- 

 ed portion retract, become enlarged and more vascular ; but 

 especially the upper portion ; and coagulable lymph is effused, 

 which soon becomes vascular. In a few days the coag- 

 ulable lymph from each portion becomes united, and anasto- 

 mosis forms between the blood-vessels j the lymph gradually 

 assumes a firmer texture, and the number of the blood-vessels 

 diminishes, and the newly-formed substance appears to con- 

 tract, like all other cicatrices, so as to bring the extremities 



