Page:Popular Science Monthly Volume 56.djvu/519

Rh . If the word "handful" had parted with its essential meaning as completely as say the word "troop" has, for all but etymologists, there would be no kind of incongruity in its employment for any small number or quantity whatsoever.

The scientific view of language, then, is that it represents the effort of mankind to use audible symbols for the expression of thought; that it follows the development of man's activity and enlarges with his enlarging knowledge, and comprehension of things; that while its object is essentially a practical one it gathers beauty with use and age, and begins to react on the minds of its makers; that its makers are the people, not the grammarians, these being merely its policemen, who, useful in general, are sometimes too officious; that great writers are the architects who felicitously arrange materials which the people have gathered and shaped, placing the best of such materials where they can be seen to best advantage; finally, that the language of each nation is its most precious possession, the record of its civilization, and the repository of all that is best in its moral and intellectual life, and that it is therefore the duty of all who make any pretensions to liberal training to watch over their heritage and, while allowing all reasonable scope for further development, to guard it by all means in their power against degradation and pollution. A great people will have a great language: when a language shows signs of weakness or declension, there is reason to fear for the civilization of which it is the expression.



"Dark Lightning."—The attention of meteorologists and photographers has been engaged to a considerable extent, within a few months past, with the appearance on photographs of lightning of what seemed to be dark flashes as well as bright ones. In the effort to account satisfactorily for the phenomenon it has been referred to photographic reversal, due to extreme brilliancy; to a predominance of infra-red radiations; to the existence of flashes deficient in actinic rays; to changes in the density of the air occasioned by the spark, when a dark line with a light line within it is shown if the air is compressed, and a light line inclosing a dark one if it is rarefied; and to some qualities of the photographic plate. The first real light was thrown on the subject by some experiments described by Mr. A. W. Clayden, who, having photographed some electric sparks of different intensities, before developing the plates exposed them to the diffused light of a gas. flame. The brilliant sparks then yielded images which might either be called normal with a reversed margin, or reversed with a normal core, while the fainter images were completely reversed—or, in other words, came out darker than the background. The "fogging" of the picture, to produce this reversal, must be done after the image of the flash is impressed; for if it is done before, the image appears lighter than the background. This effect, which is called the "Clayden effect," is accepted as a satisfactory explanation of the phenomenon by two of the authors who have most studied it—Dr. W. J. S. Lockyer and Prof. R. W. Wood, of the University of Wisconsin. Professor Wood, on repeating Mr. Clayden's experiment, obtained dark flashes without any difficulty, but as they failed to appear when the light of an incandescent lamp was substituted for the electric spark, he concludes that there is something in the spark essential to the reversal. Dr. Lockyer summarizes his conclusion by saying that dark-lightning flashes "do not exist in Nature, but