Greenough Binocular Microscope. 
The Greenough binocular microscope is a form of instrument which, although constructed 
upon a different design from the Binomax, consists of two microscopes inclined at the natural 
convergance angle. It gives the same results with a greater range of magnifying powers. In 
this microscope the objectives are interchangeable and magnifications up to 200 can be employed. 
The following table gives details of the object glasses, with the working distances and magnifying 
powers obtainable. 
No Focal Working x6 eyepiece | X10 eyepiece | x15 eyepiece | Price, per pair 
ig Length. distance. 45 m/m. 25 m/m. 17 m/m. on slide. 
£. S.eGe 
Now3010) =. 59 m/m. 80 m/m. 10 16 28 | Se LOO 
INCH 1.0) Ie 49 m/m. 50 m/m. 20 32 56 3.10 0 
Nos S02... 32 m/m. 30 m/m. | 30 60 100 410 0 
Now3013 97-9, 6 mim: | 17 mi/m. 70 | 120 200 510 0 
The object glasses are mounted in pairs upon slides which, by means of their dovetailed edge, 
are attached and interchanged in the corresponding slide upon the nosepiece of the body. These 
dovetailed slides are accurately made, so that the various object glasses take up their correct 
position when they are attached. | The body has an adjustment for setting the instrument at the 
correct interocular distance for the observer. This is accomplished by revolving the prism boxes, 
and is a very convenient adjustment in use. 
The Greenough binocular can be mounted in various ways as in the case of the Binomax. 
No. 3205 has the binocular with rack and pinion focussing adjustment mounted on to a limb 
which is attached to a base and stage, as shown in the illustration. This has a joint for inclination 
and also has a mirror for illuminating transparent objects placed upon the stage. Hand rests 
can be provided which are attached to the sides of the stage, and the whole microscope is an 
excellent one for dissecting and also for general observations of mounted specimens or small objects 
suitable for placing upon the stage. No. 3206 has the Greenough binocular mounted upon a 
horseshoe stand as illustrated. This is also suited for dissection and for the examination of small 
unmounted solid objects, which must be illuminated by top lighting. No. 3028 and No. 3029 
have the Greenough binocular mounted upon universal stands as Binomax Nos. 3761 and 3762 
(pages 56 and 57). These stands have similar adjustments, the difference being that one is made 
to clamp upon the edge of a bench or table, and the other has a heavy base for standing upon a 
table. They give large adjustment for height and position, and are suitable for the examination 
of irregular shaped objects of considerable size. Such objects can be stood upon a bench and 
the binocular microscope moved and inclined to a convenient position for observation. The 
Greenough binocular itself, with its rack and pinion focussing motion, is interchangeable upon 
all these stands, so that advantage of the various forms of stand can be taken by having a selection 
of stands with one binocular. 
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