ASTRONOMICAL PHENOMENA AND PROGRESS. 



plete synodical revolution. 2. The collection 

 of all ancient observations and drawings of the 

 planet. 3. The collection of as many modern 

 data as possible from existing observations, and 

 from public and private records. At the conclu- 

 sion of the observations of the sub-committee, 

 the results obtained, together with the ancient 

 and modern observations collected, will be 

 placed in the hands of a competent astronomer 

 for complete analysis and discussion, when the 

 results obtained will be published. 



Transits of Venus. Prof. Asaph Hall, of the 

 U. S. Naval Observatory, writes to the Ameri- 

 can Journal of Science asking the atten- 

 tion of American astronomers to the transit 

 of Venus that will take place December 8, 

 1874. He deems it of great importance that the 

 astronomers in this country should take early 

 measures to act in harmony, so that their ob- 

 servations at the various stations shall be made 

 with similar instruments, and on a precon- 

 certed plan. lie thinks that only by such 

 action, and by careful, thoughtful, and deliber- 

 ate preparation, can American observers ob- 

 tain results comparable in accuracy with those 

 that will be obtained by the German expedi- 

 tion. Therefore he suggests the following plan : 



Let the National Academy and the American Asso- 

 ciation for the Advancement of Science, at their next 

 meetings, invite the attendance of the directors of all 

 the astronomical observatories in the country, and 

 of all who are engaged in astronomical pursuits, 

 theoretical or practical. Let these astronomers dis- 

 cuss and decide upon the stations to be occupied and 

 the methods of observing the transit. They should 

 appoint committees who should have charge of pro- 

 curing instrumeiits, selecting the observers, and 

 making preparations for paying the expense of the 

 expeditions. Besides the scientific advantages to be 

 gamed, the hearty cooperation of our astronomers, 

 in the solution of such a problem, will bring about 

 mutual acquaintance and recognition of each other's 

 abilities. 



The first meeting of the commission convoked by 

 Chancellor Bismarck for considering " 



ing transit of Venus was held at Berlin, October 25, 

 1869. This commission consists of Hansen, presi- 

 dent, and of Argelander, Paschen, Bruhns, Forster, 

 Auwers, and Winnecke ; all experienced astrono- 

 mers, except M. Paschen, appointed for his knowl- 

 edge of photography. Afterward the commission 

 invited to join in its deliberations Dove, of Berlin, 

 on account of his knowledge of meteorology ; Prof. 

 Zollner, of Leipsic, for his knowledge of spectro- 

 scopic observations ; and Otto Struve, Director of 

 the Pulkowa Observatory. The early action of the 

 German Government and its wisdom in putting the 

 matter into the hands of experienced astronomers 

 nre much to be commended. "We may not be able, 

 and may not wish, to follow the methods proposed 

 by the German astronomers, but we must have 

 prompt, deliberate, and concerted action, if we would 

 obtain good results. 



The transits of Venus in the years 2004 and 

 2012 have been carefully calculated by Prof. 

 J. R. Hind, and the results communicated 

 to the Royal Society. He took for his basis 

 Leverrier's tables of the sun and Venus, which 

 are regarded as extremely accurate. Accord- 

 ing to Prof. Hind, the first external con- 

 tact of the planet with the sun, in 2004, will 

 be, as seen at Greenwich, June 7th, 17 h 9 m 56', 



and the second external contact, or last touch- 

 ing-point, as Venus leaves the sun's surface, 

 will be June 7th, 23" 22 m 15'. The entire 

 transit, it will be noticed, will be visible at 

 Greenwich. Of the transit of 2012, the ingress 

 will not be visible at Greenwich, but the 

 egress will take place as follows, as seen from 

 that point : last internal contact June 5th, 16" 

 44 m 23", and the last external contact June 5th, 

 17" 2- 15 s . 



New Theory about Jupiter. In a recent 

 contribution, by Mr. R. A. Proctor, to the St. 

 Paul's Magazine, that gentleman dissents from 

 the prevalent views with regard to supposed 

 resemblances between Jupiter and our planet. 

 Nearly all that is known of the physical con- 

 stitution of Jupiter is obtained from observa- 

 tions of the belts or streaks which encircle 

 the planet in a direction parallel with its equa- 

 tor, and which resemble, in their form and 

 arrangement, the lines of clouds which may 

 often be seen in our sky on a fine evening 

 after sunset. The most prominent of these 

 belts or streaks in Jupiter are clearly visible 

 through a telescope magnifying thirty diame- 

 ters ; but, to observe the finer ones which pre- 

 vail farther from the planet's equator, the cir- 

 cumstances must be favorable, and the magni- 

 fying powers must range from 200 to 300. It 

 has generally been considered that these phe- 

 nomena are purely atmospheric, and the par- 

 allelism of the strata has been accounted for 

 by the direction and velocity of rotation. On 

 this theory, the equatorial regions of Jupiter 

 are traversed by great aerial currents like our 

 trade-winds, which form the clouds into belts, 

 the dark bands being clouds, and the light 

 ones, the body of the planet seen between 

 them. On the contrary, Mr. Proctor says, 

 there are the strongest reasons for believing 

 that if Jupiter's belts were submitted to a series 

 of accurate and continuous observations like 

 the sun-spots, the generally-received notions 

 as to their cause would be dissipated. Facts, 

 presented by the author, lead him to the con- 

 clusion that the phenomena observed in the 

 belts of Jupiter are not such as would appear 

 from distant observation of the earth. The 

 transverse breaks, rifts, and irregularities which 

 appear in the belts, are found to have similar 

 motions and appearances, and to conform in 

 other ways to the spots on the sun. In 1860 

 an "oblique dusky streak" was seen moving 

 across a bright belt or " zone of clouds," in a 

 direction approaching to north and south. This 

 rift was about 10,000 miles long and 500 miles 

 wide, its superficial extent being greater than 

 the whole of Europe. It remained visible for 

 six weeks at least, when it passed to the dark 

 side of the planet, to return again, after the 

 Jovian night, to the illuminated hemisphere 

 during about a hundred Jovian days. Both 

 the sun and Jupiter have recently been the 

 scenes of great disturbances which have given 

 rise to similar phenomena in the two bodies. 



As regards the question of change in the 



