862 



SCIENCE. 



[N. S. Vol. V. No. 127. 



clamped at both ends upon a rigid frame, 

 the frame to be made square so as to allow 

 the knife to be placed in any desired po- 

 sition or at any desired angle. 



Fifth : A cup, with a drainage tube, to 

 be placed under the object-holder to collect 

 alcohol and prevent its falling, while the 

 apparatus was in use for wet-cutting, upon 

 the gears or ways beneath. 



About two years ago I consulted with 



has certainly spared neither time nor pains 

 to secure a good result. 



In designing the new microtome precision 

 was made the prime object. The usual 

 sources of error are : (1) in the bending of 

 the knife; (2) the yielding of the object 

 to be cut, chiefly because it is at the end of 

 an arm which acts as a lever; (3) the 

 'jumping ' of the sliding gear. All these 

 defects are at their maximum in the Eivet 



Mr. Edward Bausch in regard to the pro- 

 jected microtome, and we have worked in 

 collaboration to solve the many problems 

 involved in the practical application of the 

 five principles enumerated. It is a pleasure 

 to state that Mr. Bausch has contributed in 

 many and in essential ways to the plan of 

 the microtome, and its successful production 

 is largely due to his zealous interest. He 



type of microtome, of which the best known 

 form is the Heidelberg or Thoma-Jung. 

 It is believed that in the new microtome 

 these three sources of error are materially 

 diminished. 



The accompanying illustration, Fig. 3, 

 affords a general view of the Precision Mi- 

 crotome. The uppermost part of the mi- 

 crotome is a square frame heavily made 



