14 The Microscope. 



More properly a preservative for large anatomical and other 

 specimens. 



Wickersheim's soLUTi03sr : alum, 100 grms.; saltpetre, 12 grms.; 

 potash, 60 grms.; arsenious oxide, 20 grms.; boiled water, 3000 

 grms. A preservative of large anatomical and other specimens. 



Virodtzeff's solution: glycerine, 2160 parts; water 1080 

 parts ; alcohol, 45 parts ; thymol, 5 parts. A preservative of 

 large anatomical and other specimens. 



NOTES ON THE MICROSCOPE STAND AND ON SOME OF 

 ITS ACCESSORIES. 



AN AMATEUR. 



XIV- 



THE SELECTION OF A STAND. 



THE size is less important than the weight, provided the space 

 about the stage is not limited. It is exceedingly incon- 

 venient and annoying to be forced carefully to insert a thumb 

 and a finger between the stage and the arm, while the other three 

 fingers are coiled into a knot or extended rigidly into the atmos- 

 phere. Every time the owner of such a stand attaches an ob- 

 jective to it, not only will his three fingers become rigid, but his 

 left arm and both legs, and finally his whole body will be sym- 

 pathetically tetanized. 



In the smaller stands the sub-stage space is also too limited. 

 No room is left for certain substage accessories which the micros-^ 

 copist will surely want if he is to be anything more than a mere 

 gazer at pretty objects. Such instruments seldom have more 

 under the stage than a shallow box whose upper or lower sur- 

 face carries the diaphragm plate. 



There is no provision for a condenser, polariscope or any other 

 accessory, and therein they are defective. 



Personally, therefore, I prefer a large stand. It always has 

 plenty of weight, solidity and steadiness, with abundant space 

 for finger manipulations. The faults mentioned in connection 

 with small stands are due solely to the carelessness or the ignor- 

 ance of their makers, since few manufacturers are practical, 

 working microscopists. 



I would never give the beginner an inferior optical outfit, if 

 his purpose were a serious one. He should have the best and 



