Page:Popular Science Monthly Volume 11.djvu/136

126 salary equal to £1,000 in England, and appointed the clergyman to the professorship, but without requiring either residence or teaching. How the professor went on enriching science with his discoveries, how he trained up his sons to follow in his footsteps, two of whom are now professors in the Christiania University, all this is known to scientific men, nor will they require to be told that the name of the clergyman was Sars."

Sir Wyville Thomson on the Theory of Evolution.—Sir Wyville Thomson said, in a lecture to the natural-history class at Edinburgh University, that the great stumbling block, from the natural-history side of the question, in the way of an acceptance of the evolution hypothesis, was that any such passage from one species to another is entirely outside our experience. The horse had evidently been the horse since the earliest hieroglyphs were engraved upon Assyrian monuments and tombs; and the same held for all living creatures. There was not a shadow of evidence of one species having passed into another during the period of human record or tradition. Nor is this all. We have, in the fossil remains contained in the rocks, a sculptured record of the inhabitants of this world, running back incalculably farther than the earliest chisel mark inscribed by man—incalculably farther than man's existence on this planet; and although we find from the record that thousands of species have passed away, and thousands have appeared, in no single case have we yet found the series of transitional forms imperceptibly gliding into one another, and uniting two clearly distinct species by a continuous bridge, which could be cited as an undoubted instance of the origin of a species. Mr. Darwin's magnificent theory of "natural selection" and "survival of the fittest" has undoubtedly shaken the veil by pointing out a path by which such an end might be attained; but it has by no means raised it. Still, even if we never found out the precise mode in which one species gave rise to another, there could ba no further hesitation in accepting generally an hypothesis of evolution, and in regarding our present living races as the ultimate twigs of a great genealogical tree whose gradually coalescing branches we could trace, if our information were complete, to the dawn of geological time.

The Resources and Industries of Sudan.—At a late meeting of the Egyptian Geographical Society a paper on the Sudan was read, based on information collected by the late Munzinger Pasha. It was stated that there are few mountain-chains in the Sudan, but that granite ridges divide the region into well-defined districts, usually named after the rivers which flow through them. The country is, as a rule, fertile. The watercourses are mere torrents, which in summer are almost dry. The centres of population are few, and all the large towns are on the banks of the two Niles. Gold and copper are found, but the wealth of the country depends on agriculture and cattle breeding. The population numbers about 5,000,000, consisting of Arabs and negroes. Industry is very much developed, and only articles of luxury need be imported. Stuffs, sword-blades, and leather of a very superior quality, are manufactured. The exports are chiefly ivory, gums, skins, etc. The people are nearly all Mohammedans, but their religion is mixed with numerous heathenish superstitions.

Extermination of the Grasshoppers.—Prof. A. S. Packard, Jr., has written to the Tribune a communication in which he advocates the project of affording Government aid toward the extermination of the Rocky Mountain locust. Locust years, he observes, are years of unusual drought, and seasons of drought occur every seven or eight years. In such summers the locust breeds in untold millions, and, the supply of food being short, they fly off hundreds of miles. A swarm observed by Prof. Robinson near Boulder City, Colorado, traveled a distance of about 600 miles to Eastern Kansas and Missouri. When seen at Boulder the swarm was on its way from the north, and may have come from some part of Wyoming. The general direction of the winds in July and August, along the eastern slope of the Rocky Mountains and on the Plains, coincides with the course of these swarms. If we would intelligently study the causes of the excessive increase and migrations of the locust, we must examine the meteorological features of the Western country,