Open main menu

Page:Popular Science Monthly Volume 29.djvu/838

This page has been proofread, but needs to be validated.
838
THE POPULAR SCIENCE MONTHLY.

it also is yellow under the former illumination; the white paper and yellow object, therefore, appear of the same hue; but knowing the paper to be white, and through an error of judgment accepting the prevailing illumination as white, the yellow object appears of this color. In view of these facts, it would seem that deductions drawn from the composition of white light are in favor of making it one of the colors. As supporting this view of the matter, might be mentioned Langley's investigations which have shown that the true color of sunlight, before some of its constituents have been filtered out by the atmosphere, is decidedly blue; and that, according to Brücke, ordinary daylight is slightly reddish in tint. It might be claimed as a reason for excluding white from the color series that it has no representative in the solar spectrum, but there is equal reason for excluding purple, unquestionably a color, which has no type in any part of the spectrum, being produced only by a mixture of rays from the red and violet portions of the spectrum. And it has been proved by several observers that all of the spectrum colors when increased in intensity tend toward white, and if made dazzling actually become white. Accepting this fact in a liberal sense, it is plain that white has a representative in every part of the spectrum; and this tendency toward white with increasing illumination being also a property of black, we have a direct argument for the inclusion of the latter with the colors. In conclusion, it may be urged that the adoption of white and black into the chromatic scale is desirable for the sake of simplicity and uniformity in the nomenclature of this subject.

 

THE PHILOSOPHY OF DIET.
By a Layman.

IN the years to come it will be debated whether the great minds of the later Victorian era were most concerned with their souls or with their stomachs. Politics we may put by; they are always with us; but politics apart, between these two interests, the spiritual and the peptical, the question of precedence must surely lie. What other claimant can there be? Not literature, thrust away into corners, or tricked out in a newspaper like some May-day mummer; not art, divorced, in Carlyle's phrase, from sense and the reality of things; not music, crushed Tarpeia-wise under foreign gewgaws, or brayed in a chemist's mortar; not the drama, leveled to a tawdry platform for the individual's vanity. Not these, nor any one of these things; but the soul and the stomach, irreligion and indigestion, doubt and dyspepsia—call them what you will—these are the cardinal notes of our great inquiring age.

The former I will not touch. Sir Henry Thompson, indeed, asserts