A GLASS OF WATER. 655 



existence, and who believe that it really moves as the observer moves 

 occasionally, indeed, as I can testify, expressing surprise at the fact. 

 But, apart from -the observer, there exists no such bar of light; nor 

 when the observer moves is there any movement of this glittering line 

 of wavelets. All over the dark part of the surface the undulations are 

 just as bright with moonlight as those he sees ; but the light reflected 

 from them does not reach his eyes. Thus, though there seems to be a 

 lighting of some wavelets and not of the rest, and though, as the ob- 

 server moves, other wavelets seem to become lighted that were not 

 lighted before, yet both these are utterly false seemiugs. The simple 

 fact is, that his position in relation to certain wavelets brings into view 

 their reflections of the moon's light, while it keeps out of view the like 

 reflections from all other wavelets. 



Sociological evidence is largely vitiated by illusions thus caused. 

 Habitually the relations of observers to the facts are such as make 

 visible the special, and exceptional, and sensational, and leave invisible 

 the commonplace and iininteresting, which form the great body of the 

 facts. And this, which is a general cause of deceptive appearances, is 

 variously aided by those more special causes above indicated ; which 

 conspire to make the media, through which the facts are seen, trans- 

 parent in respect of some and opaque in respect of others. 







A GLASS OF WATER. 



By FEIEDKICn MOHR. 1 



IN tracing the history of the civilization and growth of humanity, 

 it becomes noticeable that long periods of time often witness but 

 slow and gradual progress ; but that from time to time a few inventions 

 and discoveries of eminent men suddenly kindle a revolution in all the 

 spheres of human affairs. To trace to their source the changes so 

 wrought, presents to the historian and scientist one of the most inter- 

 esting subjects. In nearly every place, the most ancient of such great 

 events, the invention of language and of written characters, are wrapped 

 in complete darkness. As history can be handed down to posterity by 

 means of language only, it is obvious that ages without language can 

 have no history. It is language which introduces nations into history. 

 As regards written speech the case is somewhat different. The most 

 distinguished people of antiquity, the Greeks, emerged from obscurity 

 into history with a language wonderfully complete, but without written 

 characters. During several centuries the Homeric songs had to wan- 



1 Translated from the German, by C. L. Hotze, Teacher of Physics and Chemistry in 

 the High School of Cleveland, Ohio. 



