The Microscope. 9S 



studying Histology and Embiyology, that the vertical position 

 of the microscope is essential to the proper study of these sub- 

 jects. 



I suppose every man has a right to believe a thing or not^ 

 and also to state it; but when one says that he does not believe 

 the vertical position of a microscope essential to the proper 

 study of Histology and Embr/ology, and I may add to the whole 

 field of Biology in its broadest sense, then he simply shows 

 without the shadow of a doubt, that he is as far from being a 

 worker with the microscope in Biology, as the scores of other 

 pleasure seekers who use the instrument to see pretty things. No 

 person can work (and when I say work I do not mean merely 

 to prepare and mount specimens? to look at), with any degree of 

 earnestness, to say nothing of thoroughness, in a single one of 

 the fields of Biology and not be compelled to use the microscope 

 in a vertical position. Nor can he, no matter how much one 

 may wish to, mount any where near all the objects to be exam- 

 ined and studied. Looking at mounted histological or embryolo- 

 gical objects, or whole animals or plants is all very nice, but how 

 often can we mount the object so as to incline the stand ? We 

 are only too glad to incline the stand when we can do so, simply 

 because it is easier to look into and less tiresome, but to use it 

 that way is impossible in fully one half the cases. The instant 

 the stand is inclined gravity begins to make itself manifest in 

 many ways ; and if we are looking at an animal that normally 

 has its dorsal aspect uppermost, when we tip the stand the 

 animal tends to preserve its proper position, and if it does and 

 we tilt the stand to horizontal we will be looking at its lateral 

 aspect. There are cases where the stand can be inclined and not 

 interfere to any extent with the object, and in each case we are 

 only too glad to do so, as for instance in the study of the Rhizo- 

 poda and Infusoria. Here there is rarely any need of more 

 water under the cover-glass than will remain in place when in 

 any position, and if we wish more water we can place the objects 

 in a life-box or compressurium. However, a life-box eats up a 

 great amount of time if one be constantly changing objects and 

 has to clean the glass each time. "With the best of care, how^- 

 ever, certain shelled Rhizopoda will roll and become entangled 

 or lost in dirt and other matter under the cover-glass, if the stand 

 be inclined to an extent to be of any advantage. 



