Microtomes. 
No. 3880 Automatic Rotary Microtome. 
No. 3880. 
This instrument is of very rigid design; it can be very quickly set up to cut a 
perfectly uniform series of sections at the highest possible speed. The object holder consists 
of a clamp adapted to take a block 16mm. in height, while the width may be anything up 
to 25mm. This clamp has a universal adjustment for the angle of face around a _ point 
coincident with the surface of a block of material of the average thickness, so that there is 
no lateral displacement when orientating. The clamp is adapted to take standard wood blocks 
19mm. <x 19mm. xX 12mm., but a roughened metal plate can be supplied 19mm. x 25mm. at a 
small cost. The knife holder is provided with an adjustment for position with respect to the 
block surface. It is fitted with screws permitting the angle of the knife to be precisely adjusted. 
The micrometer slide for the feed is extremely heavy and is carried in channels in the base of the 
instrument. The micrometer screw is direct acting and the feed, consisting of one lever and pawl 
only, is cam operated and enclosed. Section thickness is arranged in steps, 2°5y, 5, 7-5, 10y, 
12-5,, and 15,. The adjustment is made by a knurled head on the front of the frame, and, if 
necessary, without stopping the machine. The finish of the frame of the instrument, knife 
holder, object holder, is of crystalline enamel, the other parts being nickel plated. 
No. 3880. Automatic Rotary microtome ... se a5 BS ae ae sas LT LOR] 
No. 3881. Knife 12cm. blade Sh: si see a bide es aR: eee) alla Gh 
No. 3883. Knife handle aR ae ae me br oe = sisi «3 O22 eeGr 
No. 3884. Wood blocks Bx ss ae Be Kee tis e. ~ sper dozen OiezanOn 
No. 3890 Cambridge Rocking Microtome. 
The Cambridge Rocking microtome is a model which is well known. It is of rigid construc- 
tion, simple in use; the sections it gives are accurate and uniform, also long ribbons of sections 
can be obtained very speedily. The present model has been improved in design, the chief 
improvement consisting of the fitting of double knife edges on the rocking arms, ensuring a 
definite and correct alignment without friction or backlash. A simple device, which gives a 
clearance between the knife and the specimen on the backward or non-cutting stroke, has been 
added. 
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