JxiNE 8, 1906.] 



SCIENCE. 



885 



Way and the Clouds of Magellan.' Mr. Hinks 

 contends, and we think with good reason, that 

 the facts do not support the Spencerian view, 

 that the stars and nebulse are so definitely 

 separated that they must be regarded as com- 

 plementary parts of a general scheme, a view 

 which implies the symmetrical condensation 

 of stars upon the plane of the Milky Way, 

 and of nebulse toward its poles. The author 

 suggests as a working hypothesis, that the 

 stars are distributed in a series of more or 

 less independent star clouds about the plane 

 of the Milky Way, and the nebulse (not 

 gaseous), in a series of nebula clouds out of 

 the Milky Way, but not symmetrically con- 

 densed toward its poles. The Small Magel- 

 lanic Cloud becomes by this plan a distant 

 star cloud, and the Large Magellanic Cloud, 

 a combined star and nebula cloud. The theory 

 of Mr. Hinlvs certainly seems to satisfy recent 

 investigations in distribution better than 

 older and more rigid schemes. 



THE MAGELLANIC CLOUDS. 



From many standpoints the Magellanic 

 Clouds are unique. To the naked eye they 

 appear as detached jwrtions of the Milky Way, 

 faint luminous clouds which disappear in full 

 moonlight. By no means, however, should 

 they be regarded as merely irregular exten- 

 sions of the Milky Way. They have some 

 striking peculiarities. The Milky Way is 

 characterized by enormous numbers of faint 

 stars and the absence of small nebulae in 

 general, especially spirals. It has been shown 

 by Professor Pickering that the Milky Way 

 is probably composed entirely of faint stars of 

 the first type, together with the greater part 

 of the stars of the fifth type, which are 

 numerically unimportant. The type of spec- 

 trum of the faint stars of the clouds has not 

 been determined, but it is noteworthy that 

 all fifth-type stars not found in the Milky 

 Way are in the Magellanic Clouds. The 

 Small Cloud resembles the Milky Way in the 

 large numbers of faint stars and in the pres- 

 ence of numerous clusters. It also contains 

 few nebulas, but one of these is a bright-spiral. 

 It is strikingly different from the Milky Way 

 in the presence of great numbers of variable 



stars, nearly 1,000 having been found on the 

 Harvard plates. The Large Cloud shows less 

 resemblance to the Milky Way. It is true 

 that there are great numbers of faint stars, but 

 also there are great numbers of faint nebulae. 

 These nebulfe, however, do not appear to be 

 spiral on the Harvard photographs. Variable 

 stars are numerous. These clouds apparently 

 contain within themselves all the different ele- 

 ments of our universe, and may well be im- 

 agined to constitute independent galaxies, if 

 such exist. 



THE SOLAR ORIGIN OF TERRESTRIAL MAGNETIC 

 DISTURBANCES. 



It has been believed for a long time that 

 terrestrial Inagnetic phenomena were more or 

 less intimately associated with the sun, but 

 Mr. E. Walter Maunder, of the Royal Observa- 

 tory at Greenwich, has discovered a new phase 

 of the problem which marks an epoch in this 

 department of solar and terrestrial physics. 

 He has shown conclusively that not only are 

 magnetic disturbances related to the sun, but 

 also that they are related to the sun's rotation. 

 Prom a study of magnetic phenomena, extend- 

 ing from 1848 to 1903, including 726 disturb- 

 ances, he has pointed out that whenever a 

 magnetic disturbance occurred when a given 

 heliographic longitude was at the center of 

 the sun's apparent disc, there was a tendency 

 for another disturbance to follow after one 

 revolution of the sun brought again the same 

 longitude to the center. So much seems sure. 

 Certain conclusions, also, follow from these 

 observations : 



1. That the sun's action, of whatever nature, 

 is not from the sun as a whole, but from re- 

 stricted areas. 



2. That the sun's action is not radiated, but 

 restricted in direction. 



PHOTOMETRIC DETERMINATION OF THE STELLAR 

 MAGNITUDE OF THE SUN". 



In a. N. No. 4065, M. Ceraski, director of 

 the Astronomical Observatory of Moscow, 

 gives the results of a new determination of the 

 stellar magnitude of the sun. The mean 

 value obtained is — 26.59. M. Ceraski, how- 

 ever, objects to the use of the term minus for 



