SPECIMENS FOR MICROSCOPICAL EXAMINATION. 19 



solution of carmine, which has entirely obliterated the blue, only 

 sufficient traces of it being left to tell of its departed beauty. The 

 next time I do this I shall put a little acid into my blue injection. 

 I once derived much good from Laving two wide-mouthed jars, one 

 containing a weak warm solution of salt and water, which I allowed 

 to flow through the capillary system in a similar manner to that I 

 have described as employed for the blue fluid prior to sending in 

 the injection, while my subject was manipulated under warm water; 

 this excluded every possibility of air getting into the circulation, 

 which is always to be avoided as most ruinous in its results. 

 These perhaps wearisome details comprise the whole of the process 

 I have always employed ; of course, others have tried the same 

 process, but I thought that it would be better to tell you how I 

 acted, as if no one else did the same thing, because I could make 

 my short paper more didactic ; and you will see by my poor 

 specimen that with greater care this process is capable of producing 

 some very beautiful and instructive results. You will, in the sub- 

 sequent examination of it, be able to determine how much is the 

 result of the mounting medium in which I have placed it ; for my 

 part, I believe it is entirely due to this that not only the villi but 

 the Lieberkuhnian follicles are most clearly shown with the 

 capillary vessels coursing all through and around them ; and I 

 must aver that had this specimen been mounted in balsam or 

 dammar, every detail would have been sacrificed. I consider 

 balsam to be the greatest bane Histology has to fight against. 

 The specimen I show to-night, after being saturated with the 

 glycerine from the injecting fluid, only required a little weak 

 glycerine and camphor water to put it up in ; and you will see the 

 consequence is a preservation of everything that would be other- 

 wise blotted out. I must apologise for very much in this very 

 imperfect paper. It is almost too short to deal exhaustively with 

 the subject of injecting ; much must of necessity be left unsaid 

 that might with advantage be spoken, but if any member desires 

 to take up this subject and work at it, I can only recommend him 

 to read up Beale's " How to work with the Microscope," and 

 Frey's " Microscope and Microscopical Technology," which works 

 deal very fully with the various injecting fluids that may be 

 employed; then if glycerine or glycerine jelly be employed as 

 mounting media, preparations will be exhibited which will prove 

 Dr. Carpenter's dictum applicable only to the past. 



