116 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



mirror-bar is adjustable in length, and the mirror can be set at any 

 angle above or below tbe stage, allowing any obliquity of illumina- 

 tion for opaque and for transparent objects. The standard divides 

 midway between the body and the foot, and the base may be detached, 

 and the body set on an extra standard (fig. 9), with a screw at the end 

 for fixing it in a tree, laboratory table, &c. The base being inverted 

 and placed on a spindle, which is always in position in the box, 

 becomes a turntable, provided with self-adjusting clips for holding 

 the slide. Three rods, with silvered balls at one end, are the 

 supports for the Microscope, and they give momentum to the turn- 

 table when in use. Two small holes in the edge of the turntable 

 foot allow the attachment of an adjustable lamp-holder, which is 

 furnished with a lamp for class, lecture, and exhibition use. A case 

 about 7^ in. long, 5^ in. wide, and 3 in. deep, internal measure, holds 

 the instrument when packed (fig. 10), and it may be taken down and 

 packed for travelling or be taken from the box and set up ready for 

 use in a few seconds, " making the Microscope not only a first-class 

 monocular for home and ofiice use, but also for the tourist and the 

 naturalist." The Bausch and Lomb Optical Company are the 

 makers. 



" Midget " Microscope.- 

 panying woodcut (fig. 11) 



Fifi. 



-Owing to a misunderstanding the accom- 

 of this Microscope was not given with 

 its description at p. 852 of Vol. 11. 

 (1882), only the outline drawing 

 to scale appearing with fig. 150 for 

 comparison. 



Microscopes for the Examina- 

 tion of Divided Circles.* — A some- 

 what novel application of Micro- 

 scopes is seen in Wanschafi"s appa- 

 ratus for examining divided circles 

 (fig. 12). The various parts of the 

 base of the instrument are indicated 

 by the letters a, h, c, d, and e, but 

 these do not require notice here. 



The lower fixed disk has two 

 arms, upon which are adjusted four 

 Microscopes intended to be directed 

 upon the divisions of the circle 

 under examination. The body- 

 tube in all is, for greater con- 

 venience, bent outwards, with a 

 prism at the angle. The power 

 is about 60. The arm 1 is im- 

 movable, whilst 2, with its sup- 

 ports, can be revolved, so that the 

 Microscopes on the two arms respectively can be placed at any desired 



* Bericht iiber die wiss. Instiumente anf der Berliner Gcwerbeausstellung 

 im Jahre 1879 (L. Locweribcrg), pp. 74-G (1 fig.). 



