SCIENCE NOTES.

Otago Witness, Issue 3277, 3 January 1917, Page 58

SCIENCE NOTES.

Clearing Fog By Electricity. — The fact was long ago scientifically established that all dust and fog particles in the open atmosphere are electrified and subject to dispersion or precipitation; but how to clear fog from a street, along a railway, or from tho neighbourhood of a ship at sea, and to do it in a manner commercially feasible, has been a matter of serious study for many years. Dr F. G. Cottrell, who has dono so much towards the practical precipitation of dust, smoke, and chemical fumes at large industrial works, i« now engaged at the behest of the Smithsonian Institution in making some important investigations on the subject. Cheapening Magnesium.— Cheapened metallurgical processes wjII make available as new materials a number of metals now little known. Magnesium, for instance, is likely to become one of tho common metals very soon. Improvement m reduction should reduce the cost to sixpence or a shilling a pound, and with lower price industrial uses will multiply, rapidly increasing the production from thousands of pounds to thousands of tons yearly. Its alloys might largely take the place of those of aluminium in tho motor car industry, with a saving of a third in weight; while a much greater deoxidising effect than that of aluminium might bring an extensive demand for such purposes as deoxidising brass, copper, nickel, bronze, and monel metal. Meteors and Their Colours. — Three stages of colour—yellow-white, green, and deep red—have been noted in meteors nearly or quite reaching tho earth's surface and Dr Alfred Wegener attributes the changes to passage through the different layers of the atmosphere. It is now believed that the chief gas of the air up to about 45 miles is nitrogen; beyond that, to 125 miles, hydrogen; and still higJier, the very thin gas called " gcocoromum. Meteors entering only the outer layer of very rare gas are not sufficiently heated to become luminous. The first light of "shootiii"- stars "—white, yellow, or. rarefy reddish— is thought to be the glow of the meteor substance itself; the green that folic ws, the incandescence of hydrogen in tho second air stratum; and the change to red is duo to the glow of nitrogen when tho lower air is reached.

Agricultural Engineering.— In the course of the recent annual meeting of the British Association for the Advancement of Science, an interesting announcement was made by Sir Sydney Olivier, the Permanent Secretary to the Board of Agriculture and Fisheries, to the effect that the Government had decided upon a now and far-reaching movement in the interests of agriculture. This is theetsablishmont of agricultural engineering institutions throughout the country to facilitate the dissemination of the best advice on engineering in its relation to farming. Great Britain's 'agricultural progress has been seriouslv handicapped by the absence of definite information relating to the best forms of ec«'inecring so far as it affects tne farmer "individual experiment is necessarily for. eostlv to be prosecuted except in rare instances, the result being that the man on the land has been blundering from ignorance: whereas, had the necessary technical assistance been forthcoming, ho might have been able to get more out of his land. The collection of definite knowledge concerning local soils, animals, plants, and other cognate factors would enable us uotn to extend (lie area of the land under cultivation and to increase the yield per acre. During the past 20 years the migration from the land to the cities has constituted one of our gravest dangers Far more-real wealth is to be won from the scientific exploitation of (he land than is to be oerived from manufacturins industry. Imt there has been a lack of Government assistanc« in tho dissemination of rural information If the problem is attacked in grim earnest and along the right lines, the land will be invested with a revived glamour, and we mar confidently expect a welcome growth of the race of keen, healthy, and industrious veomen for which these islanaa have ever been famous. Other countries h.ve developed this rango of activity to a high standard of perfection Experimental agricultural stations are to bo found here, there, and everywhere. They ungrudgingly extend every assistance to tho farmer, unravel any problems which ho presents to them—in short, exercise every legitimate influence to encourage him to exploit the soil to the utmost advantage, thereby rendering agriculture one of the most attractive and profitable fields in the history of human endeavour.