ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



231 



Home-made Microscope.* — A. A. M. shows a photograph (fig. 31) of 

 a Microscope made by himself. The design is of no particular make. 

 By cutting out his own patterns and getting castings thereof, and by 

 exploring the odd corners of the workroom for other material, the total 

 cost was kept well under ten shillings. Of course this total refers to 

 the stand only, the eye-piece and objective being extra. 



Fig. 31. 



English V. Continental Stands. — The correspondence on this sub- 

 ject in Nature continues. IT. C. Cliadwickf does not agree with the 

 criticism on the circular rotating and centring stage of the better class 

 of Continental stands, " the use of which for anything but petrology it 

 is difficult to guess." He has found this arrangement of the greatest 

 assistance in studying certain biological ol)jects. On the other hand, the 

 excentric rotating movement below the Abbe condenser, and especially 

 the cylinder diaphragm, appear to him to be perfectly useless. 



C. Beck,t in a clearly reasoned letter, emphasizes the view that the 

 Microscope is becoming a highly specialized instrument, and that the 

 discussion will be of little service if it is directed towards the production 

 of a universal type of instrument. He points out that to make but one 

 form would be a fatal mistake. The metallurgist cannot use the instru- 

 ment which is best suited for the bacteriologist, neither will the Rosenhain 

 Metallurgical Microscope suit the biologist. The Dick Petrological Micro- 

 scope is quite unsuitable for the entomologist, and the binocular instru- 

 ment, which demands long tubes and a great range of focus for the use 



* English Mechanic, Feb. 1912. 

 J Nature, No. 2206 (1912) p. 480. 



t Nature, No. 2205 (1912) p. US. 



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