706 



SCIENCE. 



[N. S. Vol. VII. No. 177. 



tlie special features mentioned are the fol- 

 lowing : The tide wave advances progres- 

 sively from south to north on the west coast 

 of Europe, but arrives simultaneously along 

 a great stretch of eastern North America. 

 It advances northward on the east coast 

 and southward on the west coast of New 

 Zealand, but arrives all at once on the 

 eastern coast of Australia over a belt cov- 

 ering 26 degrees of latitude. Spring tide is 

 delayed from half a day to two and a-half 

 days after new moon at most Atlantic sta- 

 tions, but at Toulon, on the Mediterranean, 

 it occurs 4J hours before the syzygies. The 

 diurnal inequality, which should reach its 

 maximum with the greatest declination of 

 the moon, is belated on the European coast 

 by from four to seven days, while at one 

 point in the Gulf of Mexico it is accelerated 

 by 17 hours. Much consideration is given 

 to Boergen's discussion of interfering waves, 

 whereby the notable differences between the 

 tides of oceanic islands may perhaps be ac- 

 counted for. The once-a-day tides on lunar 

 time in the Gulf of Mexico and on solar 

 time at Tahiti and elsewhere are thus to be 

 explained. The studies of George Darwin 

 and Lord Kelvin in the modifications suf- 

 fered by the tide waves when running ashore 

 have shown that ' overtides,' having shorter 

 periods than normal tides, may be thus pro- 

 duced, and these are compai-ed with the 

 overtones of musical sounds, as explained 

 by Helmholtz. The three tides in a day in 

 the Tay at Stirling, Scotland, and in the 

 harbors back of the Isle of Wight are 

 thought to be of this nature. The continu- 

 ous records of tide gauges reveal an increas- 

 ing number of stations at which waves of 

 short periods, from 5 to 90 minutes, are 

 found, the shortest of these being much 

 longer than the longest period of wind-made 

 swell (12 to 15 seconds). Some of these 

 oscillations, as in various arms of the Med- 

 iterranean, are probably to be compared with 

 the seiches of lakes. "W. M. Davis. 



CURRENT NOTES ON ANTHROPOLOGY. 

 31ST PEABODT MUSEUM EEPOKT. 



The thirty-first report of the Peabody 

 Museum of American Archaeology and 

 Ethnology describes the progress of its^ 

 explorations and collections. Those in 

 Central America were continued under the 

 care of Mr. George Gordon. He examined 

 various caves but did not find in them any 

 objects of great antiquity. The collections 

 of casts have been enlarged, but there re- 

 mains much which the museum could do in 

 this line if it had more funds. Mention is 

 made of the liberality of the Duke of Loubat, 

 of Miss Breton and others. Miss Whitney 

 has given to the Museum the famous ' Cal- 

 averas skull,' together with the objects 

 found around it. The general activity 

 indicated by the Report continues to reflect 

 the highest credit on the curator, Professor 

 F. W. Putnam. 



THE AIMS OF ETHNOLOGY. 



A SUGGESTIVE addrcss was recently de- 

 livered before the Batavian Society of Arts- 

 and Sciences by Professor Bastian, who is 

 making a prolonged jouruejf in the Orient. 

 His subject was ' The Purposes of Eth- 

 nology.' The stj'le is simpler than is 

 usual with this celebrated master, and his 

 matter is highly suggestive. He em- 

 phasizes the principle that ethnology con- 

 cerns itself only with man as a social being, 

 and that he derives all his worth from the 

 others with whom he lives. The elemen- 

 tary thoughts of savage tribes should occupy 

 our first attention. From these we should 

 trace the ethnic modifications which arise 

 in the course of development. They stand 

 in close relation to geographic conditions, 

 which are always the leading factors in 

 ethnic evolution. These thoughts are well, 

 brought out in Professor Bastian's address. 



THE AEAUCANIAN TONGUE. 



The twenty-first volume of the Library 

 of American Linguistics, published in PariSji 



