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SCIENCE 



[N. S. Vol. XXXI. No. 787 



on the relative paucity of stars of tlie higher 

 orders of magnitude, are probably illusory. The 

 rate of extinction is small, and is marked by 

 peculiarities of stellar distribution of a larger 

 order. The evidence of a selective absorption or 

 scattering of light, deduced by Kapteyn, appears 

 to be real, but it is of local origin, and some new 

 criterion is desirable. 



An examination of the distribution, size and 

 appearance of the nebuliE shows results which are 

 in harmony with the supposition of an absorption 

 of light by the ether of space. An attempt is 

 made to deduce the distances of some of these 

 objects; and the bearing on the problem of light- 

 extinction furnished by such facts as can be 

 learned from the nebula: is discussed, together 

 with the related questions of the knowable dimen- 

 sions of the universe, and its coordination into a 

 whole by means of a conservation of energy 

 through ethereal and material interchange. The 

 conclusion is reached that there is an absorption 

 of radiation by the ether of space, and that a con- 

 siderable fraction of the energy of the universe 

 resides in the interstellar medium. 



8. At 6" 42" in the evening citizens of Norwood, 

 Mass., witnessed the fall of a brilliant orange-red 

 fire ball which descended in a nearly vertical 

 direction from an altitude of about 60° to the 

 horizon, giving off laterally numerous white 

 sparklets. The visible evidence of any explosions 

 was lacking, and no sounds whatever accompanied 

 the fall, which, according to the best observation, 

 lasted about seven seconds. From internal evi- 

 dence, it appears probable that the upper part of 

 the path was seen almost end-on, and that the 

 bolide may have reached the ground at no great 

 distance. The claim that such was the case, and 

 the asserted finding of a large and unique aerolite, 

 were considered by Professor Very. Microscopic 

 analysis shows that the stone is peculiar, and in 

 spite of some doubtful points in the evidence, it 

 is deemed best to put this evidence on record. 



9. Professor Brown's second communication con- 

 sists of a brief account of the hypotheses of 

 Seeliger brought forward to account for the out- 

 standing large residual in the motion of the 

 perihelion of Mercury and the small residuals in 

 the secular motions of the four minor planets. 

 An analysis of the nature of the three hypotheses 

 and a comparison of the number of arbitrary 

 constants introduced with the number of residuals 

 to be accounted for were also given. 



10. Assuming that the theoretical corona is 

 caused by light emitted by and reflected from 



streams of matter ejected from the sun by forces 

 which in general act along lines normal to the 

 sun's surface; that these streams are formed of 

 a series of particles ejected from the same point 

 of the sun's surface in such a way as to make a 

 continuous stream, Professor Miller showed^ that 

 the curvature of these streams was due to mechan- 

 ical causes, and that under certain conditions one 

 could find the heliocentric position of these 

 streams. 



During the summer of 1909, Professor Miller 

 examined and measured, at the suggestion of 

 Director Campbell, the series of large-scale photo- 

 graphs of the solar corona made by him and other 

 members of the staff of Lick Observatory, with a 

 view of applying this theory to them. In all, 

 there are sixteen streamers of this particular type 

 recorded on these plates. Professors Miller and 

 Marriott have since reduced the measures made 

 during the summer. All the streamers measured 

 have been reduced; there are two of them that 

 can not be reduced according to this hypothesis. 

 The others gave consistent and reasonable results. 

 The purpose of the investigation was to locate, 

 heliocentrically, these streamers. An interesting 

 and striking by-product is, that under these hy- 

 potheses it is proved that these streamers can not 

 assume the shape shown on the photographs unless 

 they are acted upon, in addition to the attractive 

 force of the sun, by a repulsive force of some kind, 

 the magnitude of which can be determined. 



11. Professor Todd's paper relates to experi- 

 ments with the eighteen-inch Clark refractor at 

 Amherst. They show the great improvement in 

 definition of sun and moon, and the brighter 

 planets and stars by simple reduction of the 

 aperture to suit atmospheric conditions. Higher 

 magnifying powers are thereby possible when the 

 seeing is inferior, providing the illumination of 

 the object allows. Variation of aperture from 

 three to eighteen inches is effected by an iris 

 diaphragm outside the objective. 



12. This memoir gives the original meaning and 

 tlie growth of meaning of non-Euclidean geometry, 

 sketches its history and its founders, and points 

 out that philosophy has found in non-Euclidean 

 geometry a new criterion fusing into components 

 of a new life the preexistent forms of Plato, forms 

 of sensitivity of Kant, products of sensation of 

 Locke, contributions of experience of Cointe. Efii- 

 cient science now finds trivial the old hypothesis 

 of the importance of individual suffering, and the 



- Astrophysical Journal, Vol. XXVII., No. 4. 



