Journal of Applied Microscopy 



and 



Laboratory Methods 



Volume VI. FEBRUARY, 1903. Number -J. 



The History of the Microtome. 



I. THE EARLIEST TYPES. 



It is proposed to issue a series of articles, of which this is the first, to give the 

 history of the gradual improvement of the microtome. This form of scientific 

 instrument, which has now become so important as to be universally used, is of 

 comparatively recent introduction. The object of the microtome is, of course, to 

 prepare thin sections of soft tissues for microscopical examination. Such an 

 instrument would naturally not have been designed until a demand had arisen 

 from scientific men for the making of sections. Now sections, although used 

 more or less during the early half of this century, were not much relied upon 

 until the second half of the last century had been reached, and we may say that 

 it was approximately about 1860 that section cutting began to come into favor 

 among microscopists. But it was not until 1874 that microtomes began to make 

 their way. I was at that time in Europe and found in the summer of that year 

 that the Ranvier microtome was just gaining its place among the French, being 

 used in Ranvier's laboratory at the College de France, and in a very few other 

 places. Visiting Germany later in that same year, I found that a German modi- 

 fication of Rivet's microtome was being introduced in the laboratories of that 

 country. This modification was known by the name of the Leyser microtome. 

 With both of these primitive instruments I have myself made many tens of thou- 

 sands of sections. As I have since been constantly occupied with microscopi- 

 cal investigations, I have had an opportunity to follow the gradual development 

 of the instrument, the whole history of which falls within the period of my per- 

 sonal experience as a professional biologist. 



We ought perhaps to regard as the earUest form of microtome the instrument 

 which has now fallen entirely into disuse, Valentine's double knife (Fig. 1). To all 

 the oldest workers this instrument must be familiar, but there are probably many 

 of the younger generation who have never seen one of them. This knife was 

 practically a two-bladed scalpel, the two blades being parallel to one another and 

 fastened to a single handle. By means of a screw and spring the blades could be 

 brought nearer together or separated more widely. The two parallel blades were 

 plunged or drawn through fresh tissue so as to cut off between them what we 



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