42 BORDER LINES OF KNOWLEDGE 



of those of the umbihcal cord, where there is not a 

 trace of any nerves.* 



In the investigation of the nervous system, anatomy 

 and physiology have gone hand in hand. It is very 

 singular that so important, and seemingly simple, a 

 fact as the connection of the nerve-tubes, at their 

 origin or in their course, with the nerve-cells, should 

 have so long remained open to doubt, as you may 

 see that it did by referring to the very complete work 

 of Sharpey and Quain, (edition of 1849,) the histo- 

 logical portion of which is cordially approved by Kol- 

 liker himself.f 



Several most interesting points of the minute anat- 

 omy of the nervous centres have been laboriously 

 and skilfully worked out by a recent graduate of this 

 Medical School, in a monograph worthy to stand in 

 line with those of Lockhart Clarke, Stilling, and 

 Schroder van der Kolk.$ I have had the privilege 

 of examining and of showing some of you a number 

 of Dr. Dean's skilful preparations. I have no space 

 to give even an abstract of his conclusions. I can 



* See also the results of experiments with woorara and suJjjhocyanide of 

 potassium. The first destroys the iiritability of the nerves, the second that 

 of the muscles. The student will find a notice of Bernard's experiments 

 with these poisons in Dr. Dalton's standard work on Physiology, which 

 if he does not own, he should at once procure. 



t See also a learned note in Dr. Waldo L Burnett's " Reviews and Ab- 

 stracts," etc., American Journal of Science, September, 1853. 



J Microscopic Anatomy of the Lumbar Enlargement of the Spinal Cord. 

 By John Dean, M. D. Cambridge. 1861. 



