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in tall narrow jar?, care being taken not to damage the edge of the razor in 

 withdrawing it. The razor should be held in much the same way as in 

 shaving. If cutting without a machine the material should be held firmly 

 but lightly. 



Iu Stirling's microtome the trough was not nearly large enough. It should 

 be filled with the freezing mixture and some material wrapped round it. 

 Mr. Groves considered the original Williams' microtome the best form of 

 any. It was necessary to keep the material thoroughly covered with gum. 

 It was also necessary to fill the space between the two surfaces with freezing 

 mixture so as to ensure rapid freezing. 



In order to remove the sections from the razor, a very thin and flexible 

 artist's spatula answered well, and the sections should be placed in spirit. 

 If frozen in a Williams' machine they should be placed in a little cold 

 water. It was better not to touch the specimen at all. If provided with a 

 large shallow dish, the top of the machine might be taken off and the 

 sections floated off ; warm water was preferable to cold, as it dissolved the 

 freezing mixture more rapidly, and there was less danger of the specimen 

 getting torn or damaged. 



In the ordinary form of the ether freezing microtome, the ether spray was 

 directed upon the brass plate. In the form he was using provision was made 

 for getting rid of the fumes of ether, and was adapted for cutting thick or 

 thin lumps of material. Small thick glass salt cellars were very useful for 

 clearing specimens in clean water. 



Mr. Groves then proceeded to cut some sections of spinal cord, remarking 

 that it was essential to get the razor perfectly level or the sections would not 

 be parallel. To test the level, the two ends of the razor were tested until the 

 two cuts were exactly parallel. 



As to the thickness of the section he observed the facility with which ex- 

 tremely thin sections could be cut. It was possible to cut sections so thin 

 that tbey would not hold together. The best thickness was a cell or a cell 

 and a half thick. With practice it was possible to cut as thin as that with 

 Pritchard's machine which was practically cutting by hand. A charming 

 feature of Williams' machine was the marvellous speed "with which it could 

 be used, and the facility it afforded for removing one specimen and replacing 

 it by another was of great advantage. 



Mr. Groves then cut a number of sections with great rapidity, and placed 

 the sections at the disposal of those members who might wish to have them. 

 He then went on to observe that the next step was to preserve the sections. 

 For this purpose it was necessary to leave the sections in the trough until the 

 gum was dissolved out. If embedded in wax less time would be sufficient. 

 If the sections rolled up in cutting, by transferring them to water for a little 

 time and replacing them in spirit they would float out perfectly flat. 



Staining was then illustrated andexplained. Staining fluids were of two 

 kinds, alcoholic and aqueous. Logwood and aniline blue-black were very 

 good stains, but it was necessary to get rid of every trace of spirit. The 

 most useful stains were Beale's carmine, pink carmine, logwood, aniline blue- 



