Rensselaer Republican, Volume 17, Number 43, Rensselaer, Jasper County, 2 July 1885 — POPULAR SCIENCE. [ARTICLE]

POPULAR SCIENCE.

Prof. Miall says that there are to be found associated with seams of coal and especially with the underlying shale, the flattened impressions of creatures which once had life,! though at first strenuously doubted, A brilliant black 1 varnish tor iron, stone, or wood can be made by thoroughly incorporating ivory black with common shellac varnish. The mixture should be laid on very thin. But ordinary coal-tar varnish will serve the; same purpose in moat cases quite as | well, and it nearly fid expensive. Lenses for the great Lick telescope are said to have been at last ly cast, and need only polishing to be ready for use. The San Francisco Call says: “In looking through this telescope it is reckoned that the moon will be brought within thirty miles of the earth, and that discoveries will be made on that planet to solve problems here-1 tofore held to be unsolvable.

The treeless condition of parts of the South American pampas, of the La Plata region, at least, is attributed by Mr. Arthur Nicols to the work of an omnipresent ant, which feeds upon leaves and quickly destroys tree seedlings and other tender plants as soon as the leaves appear above ground. Indian corn grows freely on these plains, its growth being so rapid that the insects do not succeed in completely devouring the young plants. Microscopic organisms not only destroy the plant and animaj. forms familiar to us, but they appear also to build up such forms, and to be necessary to their very existence. A French biologist, M. Duclaux, has just made some experiments which tend to prove that plants will not germinate unless microbes exist in the soil, and Pasteur had already been led to the conclusion that microbes are essential to ’ animal life, as digestion cannot be performed unless they are present. A german physiologist, Prof. Eulenberg, has found that different parts of the body are very unequally sensitive to differences of heat and cold, the sensgtof temperature being most acute in the forehead and the back of the hands, and least active in the back an l tipper part of the abdomen. At the former spots differences of about a third of a Fahrenheit degree were distinctly perceived, but at the Other .taxipoints differences were only detected when reaching nearly two degrees. After tea has been steeped in boiling water for three minutes over fivesixths of .the valuable constituents are extracted. At the end of ten minutes the leaves are almost entirely exhausted. Prolonged infusion give no additional strength to the liquid, but it dees cause the loss, by volatilization, of the flavoring principles. Hard waters are to be preferred to soft waters in the teapot, as the hard waters dissolve less of the tannin out of the leaves. The bearing of these laboratory results on the art of making a good cup of tea is obvious. Dr. J. M. Axdeks has reached the conclusion that only flowering plants, grown in well-lighted places, generate ozone; and that the most odorotis flowers produce the greatest quantity. The ozone attacks the organic matter of the air, and by oxidation renders it inert ; and Dr. Anders does not doubt that flowering plants is clear weather give off - enough of the natural purifying, agent to be of hygienic value indoors. Foliage plants although yielding no ozone, may be of advantage in contributing to the maintenance of a healthful degree of humidity iu the atmosphere of rooms.