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On a New Method of Cutting Fkesh Frozen Tissues. 

 By E. Packenham Williams. 



{Read February 25th, 1876.) 



It is not my intention to occupy your time this evening with 

 any very lengthy communication. I have felt under obligation to 

 the members of the Club for the kind manner in which they 

 received my communication respecting the little machine which I 

 had the pleasure of introducing to their notice last year. That little 

 instrument has not succeeded, I suppose, because the instrument 

 makers thought that it could not be produced at a figure likely to 

 command a sale. There is a further disadvantage it labours under; 

 I find that the sharpening of the cutter is a serious obstacle 

 in the way even of those who may be considered as respectable 

 amateur mechanics. I may say, however, that I think I see my 

 way clear to provide a means — purely mechanical — to effect that 

 operation. For these reasons I have felt it to be somewhat 

 incumbent upon me to put into form, and place before the Club an 

 apparatus first suggested by the hearing of a paper read by Dr. 

 Urban Pritchard, before the Medical Microscopical Society last 

 November, " On a new Freezing Microtome." The extraordinary 

 simplicity of the method by which the tissue was, by one and the 

 same operation, frozen and attached to the cylinder on which it 

 remained whilst it was being cut, presented a very obvious ad- 

 vantage. The sections were, however, cut by hand, which some 

 say, so far from being an objection, is a positive advantage, as 

 enabling them to cut thinner sections, which, I need hardly say, 

 I fail to see. Surely if a section be thin enough only at the edye, 

 one sufficiently thin throughout its whole extent is infinitely better. 

 Therefore judging that it would meet with your approval, I went 

 to work and produced a form of apparatus which, in my humble 

 opinion, though only a modification of existing methods, is yet 

 sufficiently original to warrant me in describing it to you as an 

 eminently serviceable combination. In Dr. Pritchard's plan 

 the temperature of the cylinder is reduced by plunging it in a 

 mixture of ice and salt, from which it is removed when sufficiently 



