NA rURE 



[September 20, 1 906 



of molecular currents in the median streams of 

 revolving electrons the motions of which are acted 

 upon by, and react upon, the magnetic forces of the 

 impressed field, while the second hypothesis is that 

 of the Hall effect, in consequence of which an electron 

 thrown into vibration in a magnetic field experiences 

 a force depending on its own velocity and on the 

 strength of the field. The results of the theory are 

 applied to the discussion of the magneto-optics of 

 sodium vapour, taken from a paper by Prof. Wood 

 himself, and also to an explanation of the Zeeman 

 effect. 



Chapters on the laws of radiation, the scattering of 

 light, the nature of white light, and the relative 

 motion of ether and matter conclude the book. In 

 connection with this last subject. Prof. Wood points 

 out that" all experimental evidence, with the excep- 

 tion of the well-known Michelson-Morley experiment, 

 is in favour of the hypothesis of a stagnant ether, and 

 that the only explanation of this discrepancy, so far 

 as we can see at present, is that due to Fitzgerald 

 and to Lorentz, that a change is produced in the linear 

 dimensions of matter by its motion through the ether. 



Sufficient perhaps has been written to show that 

 Prof. Wood has placed students under a considerable 

 debt by the publication of this book, while the pub- 

 lishers are to be congratulated on the manner in 

 which they have produced it. 



RESEARCHES IN JAPANESE WATERS. 

 Ostasienfahri : Erlebnisse und Beohachtungen eines 

 Naturforschers in China, Japan, und Ceylon. By 

 Dr. Franz Doflein. Pp. xiii + sii. (Leipzig: 

 Teubner, 1906.) Price 13 marks. 



DR. DOFLEIN adds one more to the long list of 

 books which have been written to give popular 

 accounts of scientific expeditions. In the year 1904 he 

 undertook a journey to the Far East for zoological 

 purposes, and particularly with the object of investi- 

 gating the fauna of Japanese waters, which is of 

 peculiar interest, not only as possessing remarkable 

 forms of its own, but as containing an admixture of 

 genera belonging respectively to the cold northern 

 seas and to the Indo-Pacific region, which meet in 

 that locality, with a large " deep-sea " element. In 

 the book before us we have a record of the observ- 

 ations and results of this voyage, and of the impres- 

 sions made on the traveller by the countries he passed 

 through. 



The outward passage was an eventful one. In 

 the Red Sea the Prin:: Heinrich, on which Dr. 

 Doflein had left Naples, was stopped and searched by 

 the notorious Russian auxiliary cruiser Smolensk, 

 and the mails were taken from her. The incident 

 was made more exciting by the presence on board of 

 high Chinese and Japanese officials, and created con- 

 >iderable commotion in Europe at the time. Further 

 trouble, however, awaited the Prinz Heinrich. Off 

 Dondra Head, in a heavy sea which would probably 

 have sunk her boats if they had been launched, she 

 NO. 1925. VOL. 74] 



struck some unseen object, sprang a leak, and only 

 reached Galle Harbour just in time to escape sinking. 

 Her passengers were then transferred to the Poly- 

 nesien, on which they continued their voyage from 

 Colombo, and arrived, after a further mishap in the 

 shape of a breakdown of the engines, at Saigon. 

 From this town, with the beauty of which Dr. Doflein 

 was more struck than with its morals, he travelled by 

 Hong Kong, Macao, Canton, and Shanghai, where 

 he heard of the defeat of the Russian fleet and saw 

 the interned Askold in dock, to Nagasaki, and thence 

 by Yokohama and Tokio to Sendai Bay, in the 

 Rikuzen district on the east coast, where his work 

 was to begin. 



The reason which had led Dr. Doflein to choose 

 this locality for his investigations was that on the 

 east coast of Japan the warm current known as the 

 Kuro Siwo, or Japan coast current, derived from the 

 north equatorial drift, meets the cold Kurile current 

 from the north on more or less equal terms, and that 

 therefore in this region the relations of the Indo- 

 Pacific and northern faunas might best be studied. 

 On the western side of the islands the Tsushima 

 current, an offshoot of the Kuro Siwo, appears to 

 have little influence on the temperature of the water, 

 which, so far as is known, has here a more pre- 

 dominantly subarctic fauna. The result of the in- 

 vestigations at Sendai was to show that there is no 

 sharp boundary between the southern and northern 

 faunas, and there is evidence that the change from 

 the one to the other is gradual, and takes place all 

 along the east coast of Japan. This is probably due 

 to the fact that the two currents interlace in a com- 

 plicated manner and change their position with the 

 time of year. Our knowledge of these currents is 

 largely owing to the work of the Unfortunate Admiral 

 Makaroff, who perished off Port Arthur. Dr. 

 Doflein 's stay in Sendai was brought to an end by 

 bad weather, and he then left for Sagami Bay in the 

 south, where he made his headquarters at Aburatsubo 

 in a small marine laboratory belonging to the L^ni- 

 versity of Tokio. 



The fauna of Sagami Bay is extraordinarily rich, 

 probably on account of the abundant food supply 

 owing to the mortality among the surface organisms 

 of the two currents in consequence of the change of 

 temperature when they meet. It has been collected 

 by many naturalists from von Siebold onwards, and 

 Dr. Doflein wisely gave his chief attention not so 

 much to collection as to the observation of the habits 

 and mutual interdependence of the animals, both of 

 the deep and shallow waters. He describes his 

 impressions of the latter in a graphic chapter, and 

 makes some interesting remarks on the meaning of 

 their coloration. There seems to be a large tropical 

 element, brought, no doubt, by the Kuro Siwo. -After 

 some weeks' investigation of the shallow-water fauna. 

 Dr. Doflein returned to Tokio to hire a small steamer 

 for deep-water work. The first vessel that he 

 chartered sank off Misaki, near .Aburatsubo, and 

 thus wasted precious weeks of fine weather, but with 

 another he was able to do good work, both on the 



