THE MICROSCOPE. 165 



with larger species, they must have their spores which are altogether 

 invisible and their terminal or biflagellate cilia. 



The smallest monads dwindle into nonentity nearly and are 

 hardly distinguishable from each other, e.xcept from their move- 

 ments produced by invisible flagella. 



The mysterious motions of diatoms, although a quandary, may 

 be from unobserved minute organs or organisms, finer than have 

 yet been discovered, although possibly internal, yet after all, the 

 cause is hidden from view. 



The so-called " Brownian movement " may be caused in many 

 cases when the material favors, by the jostling of unseen forms of 

 life, although light, heat and electricity may also have their effe-cts. 



Particles of transparent and volatile substances, perfumes, 

 gasses, etc., although invisible, are well known to be made up of 

 scattered particles. 



The various atomic arrangements in opaque substances cannot 

 be seen or ever hoped to be seen, as no doubt a single atom or 

 small cluster of atoms are unable to throw light enough by reflection 

 or otherwise to appreciably affect the optic nerve — thus the limit of 

 vision ! 



Whether the microscope can be supplemented by any instru- 

 ment or modification, as the telescope is supplemented by the 

 spectroscope (yet the microscope has also its spectroscope), or, per- 

 haps, something higher than that, is a question finer than any one 

 dare as yet to venture a prediction. 



To plunge into and among these infinities, is rather a deep sub- 

 ject for the microscopist, but he will not stop short of his utmost 

 endeavors to find out the ultimatum of human perception, at least, 

 with every accessory that may be furnished. 



HOW TO TURN OVER SMALL OBJECTS. 



BY J. M. ADAMS. 



SIMPLE and convenient way of turning over small objects, as 

 corpuscles, epithelium, diatoms, etc., in a liquid, is to half fill 

 a live box and revolve the stage or hold the instrument so that it 

 can be swayed out of level or from one side to another. In this 

 way all sides can be easily and readily seen. 



A 



