Popular Science Monthly/Volume 49/September 1896/Minor Paragraphs

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MINOR PARAGRAPHS.

Prof. Dewar, in the first of a series of lectures on Chemical Progress at the Royal Institution, paid a well-deserved tribute to the pioneer work of M. Moissan, in his researches on the combination of carbon and the various metals in the electric furnace. Prof. Dewar also called attention to the fact that many years ago Mendeleef put forth the view that the immense localization of petroleum at Baku and other centers could only be accounted for on the theory that it was being continuously generated by the action of water on carbides. Benzene, which is the nucleus of all the colors hitherto obtained from coal tar products, is reached by the acetylene process in three stages: first, the combination of lime and coal in the electric furnace; second, the decomposition of the resulting carbide by water; and, thirdly, the transformation into benzene of acetylene gas by means of heat.

The catalogue of earthquakes in Russia, to which are added those in China, Persia, and other countries bordering on that empire, begun by A. Orloff, in 1869, and just completed and revised by Prof. Mushketoff, contains a list of about 2,400 separate earth, quakes which occurred in 560 places, between 596 b. c. and a. d. 1887. Of them, 710 took place in China, 549 in East Siberia, 36 m West Siberia, 202 in Central Asia, 590 in Caucasia, 121 in Asia Minor and North Persia, and 188 in European Russia. Considering only the periods during which the observations went on without interruption, the frequency of earthquakes may be represented as having been 640 in each hundred years in Caucasia, 810 in China, 290 in East Siberia and Turkistan, 138 in Middle and South Russia, and only 19 in North Russia, Finland, and the Baltic provinces. The date of the catalogue shows that while in Siberia and Central Asia earthquakes are more frequent during the autumn and winter than during spring and summer, the proportion is reversed for China and Caucasia.

The interdependence of the most unlike things in Nature is well shown by the following: It seems that in certain districts the growing of water cresses is quite an important industry. The caddis worm is very fond of water cresses, but is usually kept from doing them any serious damage by the trout, which it seems are very fond of the caddis. But during last season a large number of herons appeared, who have a special predilection for trout, which they thinned out to such a degree that the caddis worms were given a free course, and soon destroyed the water-cress crop. The loss of the water-cress grower was primarily due to ravages of the caddis worm; which ravages were due to the lack of trout; the lack of trout being due to the unusual number of herons present in the neighborhood, and the unusual number of herons was due to the men who encouraged their breeding and multiplication for other reasons. Thus we have a state of things which at first sight seems to have arisen through purely natural causes, but which, upon closer inspection, is clearly traceable to man's interference with the "balance of Nature."