418 PROCEEDINGS OF THE AMERICAN ACADEMY 



distance difiers from 2.6 should be about 5.2 times the inclination, or 

 2.4 times the eccentricity. 



Now, the orbits of the asteroids are very far indeed from fulfilling 

 either of the last two conditions. The mean value of the eccentricities 

 is almost exactly the same as that of the inclinations, and the variations 

 in the mean distances are much less than they ought to be. 



Again, it would seem highly probable, on Olbers's hypothesis, that 

 the smaller fragments would be projected with greater velocities than 

 the large ones, and would thus be found to have larger eccentricities, 

 inclinations, and ranges of mean distance. Such, however, is not found 

 to be the case. 



The orbits of the asteroids do not seem to have been materially af- 

 fected by a resisting medium. Such a medium would affect the smaller 

 ones more than the larger, and thus cause the former to approach the 

 sun more rapidly than the larger. But no tendency among the smaller 

 asteroids to be near the sun is observable, other than what proceeds 

 from the less brilliancy (and consequently less susceptibility of discov- 

 ery) of the more distant ones. 



It has frequently been remarked, that a large majority of the aste- 

 roids have their ascending nodes and perihelia in the first semicircle 

 of longitude. This fact throws no light on the question of their origin, 

 since it is the almost necessary efiect of known causes. The principal 

 cause is the attraction of Jupiter ; and the eflfect may be expressed by 

 saying that there will always be a tendency in the nodes of the aste- 

 roids to comcide with the node of Jupiter, and in the perihelia of the 

 asteroids to coincide with that of Jupiter. 



It is possible that the hypothesis that the asteroids were formed by 

 the breaking up of a revolving ring of considerable eccentricity and in- 

 clination might account for the general relations of their elements. 



Dr. I. I. Hayes, of Philadelphia, addressed the Academy, by 

 special invitation, upon the subject of his proposed expedition 

 to the Arctic Seas. He was introduced by Dr. B. A. Gould, 

 who said : — 



More than eighteen months ago, upon the first announcement by 

 Dr. Hayes of his desire to organize an expedition to the North Polar 

 regions to complete the work of the Grinnell expedition under Dr. 

 Kane, resolutions were unanimously passed by this body, commend- 



