15 



On the Injection of Specimens for Microscopical Exami- 

 nation. 



By T. Charters White, M.R.C.S., &c, President. 



(Read September 23rd, 1881.) 



Dr. Carpenter, in treating of the injecting of the vessels of an 

 animal in order to show their arrangement in the various organs of 

 the body, says, " The art of making successful preparations of 

 this kind is one in which perfection can usually be attained only 

 by long practice, and by attention to a great number of minute 

 particulars ; and better specimens may be obtained therefore from 

 those who have made it a business to produce them, than are 

 likely to be prepared by amateurs for themselves." Now, while I 

 have every respect for the utterances generally of this distinguished 

 microscopist, I must take exception to this statement. I can 

 agree with him so far as he commends the beauty of the injections 

 made by our friends A. C. Cole and Topping, and of others who 

 devote themselves to this particular branch of microscopical pre- 

 paration, but beg distinctly to differ from him in the statement 

 that their labours are perfection, however admirable and beautiful 

 they may be as examples of successful work. Given an amateur, 

 who, by a little practice, can carry out this branch of work with 

 tolerable facility, and who does not disregard in an organ the 

 relationship of the other anatomical elements to its vascular 

 arrangements, then, I say, he will produce much more instructive 

 work than any exclusively professional mounter. We are accus- 

 tomed to see extremely beautiful and perfect injections exhibited 

 by these gentlemen, but none showing anything beyond the injected 

 vessels ; all the substructure which bears an intimate relation to 

 the vascular arrangement is entirely obliterated. This to a certain 

 extent may be due to the mounting medium employed in putting 

 them up, but does not alter the accusation I bring against them ; 

 and if a mounting medium could be devised and employed which 

 would show the adjacent structures at the same time as the vessels, 

 then, I say, the professional mounters would have reached the 

 pinnacle of perfection. Having no regular paper set down for 

 reading this evening, I have come forward at short notice to stop 

 the gap by one of those casual communications I have often under 



