110 The Microscope. 



bubble will have a bright center and black rim, and will thus ])e 

 brought out most prominently. Study at different foci. 



The intelligent reader will study other forms of dirt than those 

 mentioned here, and will find it not only interesting but very 

 profitable. 



EDITORIAL. 



STAINS. 



To the development of this branch of microscopical science we 

 owe much ; with its futui'e perfection — if it ever obtain — will come 

 the almost perfection of the science. In particular, this may seem 

 an exaggeration; in general, however, we believe it true, and if true, 

 ihe subject is not allotted the importance it deserves. 



How often, for instance, we read of a new objective that 

 i:)romises wonders. Such and kindi-ed productions, of great value 

 withal, are examined and discussed, till the next new objective or 

 what-not displaces it. All this is as it should be. But do we shoAv 

 the same enthusiasm and interest over a new stain that allows us, 

 perhaps, to study some object more satisfactorily with a i than 

 could formerly have been done with a ^f We think not. All this 

 is wrong. Is the new apochromatic glass — granting, even, all that 

 is claimed for it — of greater importance to us than the results of the 

 studies in the anilin dyes that individualized the B. tuberculosis f 



There are many who hold that we have about reached the limit 

 of perfection in lenses. Be this as it may, the goal certainly does 

 not seem to be so very far distant. But the province of stains has 

 not as yet been invaded to any very great extent. And especially is 

 this true as regards differential staining. To be sure we have 

 double stains and treble stains almost ad infinitum, but they are 

 very far from what they should be. That they can be improved, and 

 perhaps perfected, we have really no reason to doubt. Bacterioloo-i- 

 cal investigations, so active at the present day, are doing much to 

 stimulate work in this important field. Along with the discovery of 

 new stains should go the study of the effects they may have on the 

 tissues — what changes they cause and in what manner these are 

 brovight about, that they may, if possible, be avoided. In short, 

 systematic work is needed. It seems that in the results of such 

 work we have the most potent means to thoroughly utilize the lenses 

 we now possess, and through which only will many future discoveries 

 be possible — be the lenses what they can. 



