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Action of Liquid Air on the Activity of Seeds.--In a memoir read before the Academie des Sciences, M. Paul Becquerel publishes the results of his investiga tions on the action of cold on seeds, making use of liquid air. The interesting conclusion is reached that the resistance of seeds at low temperatures depends on the quantity of water and gas contained. If the quantity is sufficient, the cold disorganizes the proto plasm and nucleus and renders all return of life im possible. But if the protoplasm has already reached by desiccation its maximum of concentration, or max imum of activity, it escapes the influence of low tem peratures, and the seed preserves its germinating power. Within comparatively recent years, that is, since aniline dyes have almost completely supplanted the mineral and vegetable dyes formerly vised in coloring cotton textiles, an extensive demand for castor oil has sprung up in the industry of dyeing and printing cot ton goods. Without presuming to invade the intrica cies of the dyers art wherein secret recipes for the composition of colors and their application to cloth are the property of each individual dyer, it may be said that the general principle underlying the utility of this oil in coloring processes is that the aniline and alizarine dyes are soluble in sulphurated castor oil; in other neutral fats and oils these dyes, with few ex ceptions, are in general insoluble. In certain processes of dyeing and printing, therefore, castor oil enjoys a practical monopoly over all other oils. The sphere of hygiene may be divided, as it often is, into the two hemispheres, public hygiene and per sonal hygiene, or it may be cut into one portion deal ing chiefly with the human mechanism and its opera tion (personal hygiene), and another portion dealing chiefly with the environment of that mechanism (sani tation). The time has gone by when any one person can safely undertake to deal with the whole sphere of hygiene. The physiologist and the physician must in the future leave to the architect and the sanitary engi neer such subj(cts as: housing, heating and ventilation, water supply and sewerage, precisely as the sanitary engineer hasnever presumed to deal with foods and feeding, vaocineii and, antitoxins, exercise, sleep and rest. The- tormer.Bubjects deal chiefly with the con trol of the environment,. the latter subjects chiefly with the control of. the indivldiual, and sanitation and hy giene must henceforward be regarded as separate hem ispheres of the science of health. A new apparatus, the aquameter, has been devised for assisting in the compilation of weather forecasts. In such work it is pointed out that a very important factor is not taken sufficiently into consideration. This is the exactitude of the percentage of aqueous vapor in the approaching winds. The barometer gives some such indication, but the height of the barometer de pends on wind pressure and temperature as well as on moisture. The wet and dry-bulb thermometers con stitute an antiquated instrument and are not sufficient ly reliable, as their variation depends on erratic cir cumstances and their indications are not represented in actual percentages of aqueous vapor. Rain results when an atmosphere nearly saturated with aqueous vapor becomes lowered in temperature. The nearness or otherwise of a wind to its saturation point, is, there fore, a most important question. It has had to be de termined hitherto by recourse to elaborate apparatus, including a chemical balance, and, therefore, out of the usual province of a meteorologist. By using the aqua-meter, however, which is a simple instrument, the exact percentage of aqueous vapor can be obtained. By the opening and shutting of two taps and the rais ing and lowering of a mercury reservoir, a measured quantity of air is drawn into a glass vessel, and placed in contact with anhydrous phosphoric acid which is a /apid water absorbent. The rise of mercury in the narrow glass stem of the vessel then gives the exact percentage of the aqueous vapor in the air.
