IN MEDICAL SCIENCE. 43 



only refer to his proof of the fact, that a single cell 

 may send its processes into several different bun- 

 dles of nerve-roots (Fig. 7, ^), and to his demon- 

 stration of the curved ascending and descending fibres 

 from the posterior nerve-roots, to reach what he has 

 called the longitudinal columns of the cornua (Fig. 

 8, h, K). I must also mention Dr. Dean's exquisite 

 microscopic photographs from sections of the medulla 

 oblongata, which appear to me to promise a new de- 

 velopment, if not a new epoch, in anatomical art. 



It havino; been settled that the nerve-tubes can 

 very commonly be traced directly to the nerve-cells, 

 the object of all the observers in this department of 

 anatomy Is to follow these tubes to their origin. We 

 have an infinite snarl of telegraph-wires, and we may 

 be reasonably sure that, if we can follow them up, we 

 shall find each of them ends in a battery somewhere. 

 One of the most interesting problems is to find the 

 ganglionic origin of the great nerves of the medulla 

 oblongata, and this is the end to which, by the aid of 

 the most delicate sections, colored so as to bring out 

 their details, mounted so as to be imperishable, mag- 

 nified by the best instruments, and now self-recorded 

 in the light of the truth-telling sunbeam, our fellow- 

 student is making a steady progress in a labor which 

 I think bids fair to rank with the most valuable con- 

 tributions to histology that we have had from this side 

 of the Atlantic. 



It is interesting to see how old questions are inci- 



