(1674)
INVISIBLE MADE VISIBLE
On the brightest and sunniest day, millions of tons of black charcoal in an invisible condition are floating in the air. Millions of plants are at the same time restoring it to visible form by the chemical processes going on in the tiny laboratory of every leaf that expands in the sunshine. In the course of time the leaf or the wood it elaborates by its delicate alchemy, may be burned; and this cycle of change may go on indefinitely, the matter becoming visible and invisible again and again. (Text.)—Popular Science News.
(1675)
In chemical operations, whether natural or artificial, matter is often “lost to sight”; but the veriest tyro has learned, as one of the fundamental axioms of science, that it can never be actually lost or destroyed. In its manifold mutations it often disappears from our vision; but it reappears, or can be made to reappear, as palpable to our senses as before. If a piece of silver be put into nitric acid, a clear and colorless liquid, it is rapidly dissolved, and we “see it no more.” The solution may be mixed with water, and apparently no effect is produced. Thus, in a pail of water we may dissolve fifty dollars’ worth of silver, not a particle of which can be seen. Not even the chemist, unless he should apply certain tests to detect its presence, would, by merely looking at the liquid, guess what hidden wealth it contained. Other metals, as we know, can be treated in similar ways with the same result. When charcoal and many other substances are burned, they disappear as completely, no visible ashes even being left from the combustion. In fact, every material, which is visible can, by certain treatment, be rendered invisible. Matter which in one state or condition is perfectly opaque, and will not permit a ray of light to pass through it, will in another form become perfectly transparent. The cause of this wonderful change in matter is utterly inexplicable.—Popular Science News.
(1676)
The progress of science is fast bringing the hitherto invisible universe into man’s view.
Unofficial announcement has been made at Boston that Prof. H. C. Ernst, of the Harvard medical school, has discovered a new method of photographing bacteria, which makes it possible to watch the life of disease germs, to watch the effect of medicine upon them and to see new facts as to the form which has heretofore been clouded in mystery. The Ernst method consists in the use of ultra-violet rays of the spectrum which are invisible to the eye. Under the present method no picture of germs is made until they are colored by chemicals.