the voluntary muscles with the brain, 165 



operations did not possess that exquisite sensibility which the 

 profusion of the sensitive nerves w^ould imply, or which the 

 skin really possesses. 



Still dissection did not authorise this conclusion. I traced 

 the sensitive nerves into the substance of the muscles : I found 

 that the fifth pair was distributed more profusely to the 

 muscles than to the skin ; and that estimating all the nerves 

 given to the muscles, the greater proportion belonged to the 

 fifth or sensitive nerve, and the smaller proportion to the 

 seventh or motor nerve. On referring to the best authorities, 

 as Meckel,* and my excellent preceptor Monro, the extre- 

 mities of the fifth were described by them as going into the 

 muscles, so that of this fact there cannot be a doubt. 



Having in a former Paper demonstrated that the portio 

 dura of the seventh nerve was the motor of the face, and that 

 it run distinct from the sensitive nerve, the fifth, and observing 

 that they joined at their extremities, or plunged together into 

 the muscles, I was nevertheless unwilling to draw a con- 

 clusion from a single instance ; and therefore cast about for 

 other examples of the distribution of the muscular nerves. It 

 was easy to find motor nerves in combination with sensitive 

 nerves, for all the spinal nerves are. thus composed; but we 

 wanted a muscular nerve clear in its course, to see what 

 alliance it would form in its ultimate distribution in the 

 muscle. I found in the lower maxillary nerve the example 

 I required. 



The fifth pair, from which this lower maxillary nerve 

 comes, as I have elsewhere explained, is a compound nerve; 

 that is to say, it is composed of a nerve of sensation, and a 



♦ Meckel de quinto pare nervorum cerebri. 



