466 



NOTES AND MEMORANDA. 



utmost possible limits of obliquity would be attaiuecL This is the 

 more important at the present time, when the apertures of object- 

 glasses arc being so largely increased. 



Contrivance for holding Objects beneath the Stage.— Since the 

 preceding note was in type the ' Monthly Journal of Science ' has 

 published * a note on a simple contrivance for holding the object 

 beneath the stage of the Microscope when extreme obliquity of illumi- 

 nation is required. It is the device of Mr. John Phin, of New York, 



and has the advantage of being easily adapted to any Microscope. 

 The little "sub-stage" (shown in the annexed woodcut) with clips 

 attached slides into the aperture in the stage, and the mode of use is 

 obvious. Mr. Phin states that the plan of holding the object beneath 

 the stage is not new, having been invented by Mr. C. S. Spencer about 

 twenty years ago. 



New Microtome. — Several years ago, wishing to make some thin 

 sections of animal tissue, and not having the educated hand, Dr. S. 

 W. Fletcher, of Pepperell, Mass.,1 set about devising an instrument 

 for doing such work. The conditions to be fulfilled appeared to him 

 to be : to attach the cutting blade to a carrier so arranged as to draw 

 rejteatedly the edge of the blade over the specimen with any desired 

 inclination and in exactly the same course ; to prevent every part of 

 the blade, except the edge actually cutting, from touching the prepa- 

 ration ; to immerse the object in alcohol or other preservative fluid 

 whilst being cut ; and to approach the specimen to the blade to any 

 desired extent, the whole instrument being made heavy and firm 

 enough to prevent any considerable trembling under ordinary use. 

 These conditions he has endeavoured to fulfil in the following 

 manner : — 



X X, Fig. 1, is a wooden frame 16 inches in length, 8 inches in 

 width, and 5^ in height ; to the top of this is clamped the wooden 

 bar K R by means of the bolts 6 and 7, which pass through the slots 

 cut in the arms which project from each end of it. B is a piece of thick 

 plate-glass cemented to the side of the bar R R, and C and D are similar 

 pieces of glass cemented to the top of the frame X X. In the centre of 



* ' M. Journ. Sci.,' i. (1879) 392. 

 t ' English Mechanic,' xxix. (1879) 108 (from 

 Journal '). 



Boston Medical and Surgical 



