126 



THE POPULAR SCIENCE MONTHLY 



salary equal to 1,000 in England, and ap- 

 pointed the clergyman to the professorship, 

 but without requiring either residence or 

 teaching. How the professor went on en- 

 riching science with his discoveries, how he 

 trained up his sons to follow in his foot- 

 steps, 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 Wyviile Tlioaison on the Theory of 

 Evolntion. Sir Wyville Thomson said, in a 

 lecture to the natural-history class at Edin- 

 burgh 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 en- 

 tirely outside our experience. The horse 

 had evidently been the horse since the ear- 

 liest hieroglyphs were engraved upon As- 

 syrian 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 pe- 

 riod of human record or tradition. Nor is 

 this all. We have, in the fossil remains con- 

 tained 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 far- 

 ther 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 an- 

 other, and uniting two clearly distinct spe- 

 cies by a continuous bridge, which could be 

 cited as an undoubted instance of the ori- 

 gin of a species. Mr. Darwin's magnificent 

 theory of " natural selection " and " survi- 

 val 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 gen- 

 erally an hypothesis of evolution, and in re- 

 garding our present living races as the ulti- 

 mate twigs of a great genealogical tree 

 whose gradually coalescing branches we 



could trace, if our information were com- 

 plete, to the dawn of geological time. 



The Resources and Industries of Sudau^ 



At a late meeting of the Egyptian Geo- 

 graphical 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 water- 

 courses are mere torrents, which in sum- 

 mer are almost dry. The centres of popu- 

 lation 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. Stiitts, 

 sword-blades, and leather of a very superior 

 quality, are manufactured. The exports are 

 chiefly ivory, gums, skins, etc. The peo- 

 ple 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 whicli he ad- 

 vocates the project of affording Government 

 aid toward the extermination of the Rocky 

 Mountain locust. Locust years, he ob- 

 serves, 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. Eob- 

 inson near Boulder City, Colorado, traveled 

 a distance of about GOO miles to Eastern 

 Kansas anti Missouri. When seen at Boulder 

 the swarm was on its way from the north, 

 and may have come from some part of Wyo- 

 ming. 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 ineteoro- 

 losical features of the Western country, as- 



