284 



THE POPULAR SCIENCE MONTHLY. 



essays and the awarding of the prizes. The 

 subjects ere given out quarterly. Three 

 highest prizes and ten smaller ones are 

 awarded ; the essays are printed in the na- 

 tive newspapers, and the year's essays re- 

 ceiving the highest prizes, with the criticisms 

 on them, are published in a book. For the 

 essays of 1889, three extra subjects were 

 selected by Li Hung Chang, far beyond the 

 range of the ordinary Chinese scholar. They 

 were a sketch of Western science, includ- 

 ing notices of Aristotle, Bacon, Darwin, and 

 Spencer ; the breach of international law by 

 one country turning its back on its treaty 

 with another, and refusing to allow the peo- 

 ple of the other country to come and go 

 within its boundaries ; and the suggestion of 

 a remedy for the damaging competition of 

 Indian tea with Chinese. There were stu- 

 dents, however, who did not shrink from 

 undertaking them, and " many English Sino- 

 logues were greatly bored by their native 

 friends " for information respecting the 

 Western savants and their scientific teach- 

 ings, " hardly knowing, perhaps, why an in- 

 terest in such celebrated characters should 

 have been so suddenly developed among the 

 Chinese." 



A Whirligig Spider. The habit of some 

 geometric spiders of gyrating under certain 

 circumstances is known, and even not un- 

 common, but, according to correspondents 

 of Nature, has not been described in sci- 

 entific works. A Pholcus, abundant in La 

 Plata, is described by Mr. W. II. Hudson as 

 having the habit strongly marked. It has 

 legs of extraordinary length, and the color 

 and general appearance of a crane-fly, but 

 is double its size. When approached or dis- 

 turbed, it gathers its feet in the center of its 

 web, " and swings itself round and round 

 with the rapidity of a whirligig, so that it 

 appears like a very slight mist on the web, 

 and offers no point for an enemy to strike 

 at. Here the correspondence between struct- 

 ui'e and habit is nearly perfect; the slimness 

 and great length of the legs causing the 

 creature, at the moment the swift revolutions 

 begin, to seem to disappear from sight ; and, 

 owing to the string-like form of the legs, the 

 fatigue experienced is probably very much 

 less than the action would cause in a stout, 

 short-legged spider like the English species. 



At all events, it can revolve for fifteen or 

 twenty seconds at a stretch ; and, if the 

 cause of alarm continues, it will perform 

 the action no less than three times before 

 quitting the web. The English spider ex- 

 hausts itself in a few seconds." 



Impediments to Growth of Population. 

 In speculating upon the causes of the sta- 

 tionary condition of the population of France, 

 the customs of subdividing the land and cf 

 providing dowries for girls have been cited 

 as important factors in keeping down the 

 increase. Abnormal mortality from small- 

 pox and from typhoid fever is mentioned in 

 the Lancet as another probable cause. Dr. 

 Brouardel has pointed out that, while Ger- 

 many loses only 110 persons a year from 

 small-pox, France loses 14,000, and that 

 the deaths by typhoid fever amount to 

 40,000. These facts carry the matter back 

 to slackness in enforcing vaccination and to 

 faults in water-supply. Dr. Brouardel con- 

 cludes his paper on this subject by affirm- 

 ing that if vaccination and revaccination 

 were made obligatory in France, and if the 

 towns were everywhere supplied with pure 

 water, the country would save from 25,000 

 to 30,000 lives annually, and these, for the 

 most part, of young persons of marriage- 

 able age. 



Cariosities of Marriage. The theory of 

 English scholars concerning the evolution of 

 marriage is in a measure confirmed by Prof. 

 Kovalevsky's studies in Russian ethnog- 

 raphy. The evidence of a primitive con- 

 dition of great license is, however, slight, 

 and rests principally on the testimony of 

 prejudiced witnesses. The evidence of a 

 matriarchal and endogamic stage is strong- 

 er, and receives some confirmation from 

 customs that survive among Russian peas- 

 ants. The transition to marriage by capture 

 and exogamy was general. The former prac- 

 tice existed in Scrvia and Montenegro until 

 recent times. The growth and prevalence 

 of the custom of purchase are shown by the 

 wedding songs in use among Russian peas- 

 ants. The Mordvins of Russia, according 

 to the Hon. John Abercromby's conclusions, 

 before they came in contact with the Slavs, 

 wooed by proxy and contracted marriage by 

 purchase, but went through the form of 



