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Difference of Longitude, 101° 14.9.
Difference in Longitude of the Poles of the Terrestrial Magnetism, 111° 51'.
It will be seen by computation that the extremities of the coronal rays are vertically above the sun spot belts at the Minimum of the Period.
NOTICES FROM THE LICK OBSERVATORY.
PREPARED BY MEMBERS OF THE STAFF.
THE INTERNATIONAL ASTROPHOTOGRAPHIC CONGRESS (1889) and A VISIT TO CERTAIN EUROPEAN OBSERVATORIES, ETC.
Under this title Lieut. WINTERHALTER, U. S. N., has printed a report of some 350 pages as Appendix I to the Washington Astronomical Observations for 1885. It is divided into three principal parts. Part I relates to the Transactions of the International Astrophotographic Congress, and is a useful English translation and summary of what has already been printed in the Bulletin of the Congress. Part II contains Notes of a Visit to Certain European Observatories, etc., together with admirable illustrations of some of the more important buildings and instruments; and Part III relates to Sundry Astronomical and Nautical Constructions and Processes.
The volume is mentioned here on account of its Part II, which gives an excellent general idea of the present state of many of the principal observatories in Europe, and which will be interesting to any of the members of the Society who can see it, if only to compare the constructions and designs there described with those with which they are familiar on Mount Hamilton.
Through the kindness of Captain MCNAIR, Superintendent of the U. S. Naval Observatory, we have received permission to have electrotypes made from some of the cuts which illustrate this work, and it is the intention of the Committee on Publication to reproduce some of the more interesting pictures in the Publications A. S. P., from time to time, accompanied by very brief descriptions. this way some of the excellent results of Lieut. WINTERHALTER'S report will be made available to all the members of the Society.
E. S. H.
BRIGHT METEOR OBSERVED IN DAYLIGHT.
The following is extracted from a letter lately received from Mr. C. F. MERRILL, agent of the S. P. Co. at Colma :
* "Some little time ago duty compelled me to remain. on watch all night at this station. About 6:13 A. M. on September 14, while sitting at the window of the waiting-room, which faces directly south, my attention was attracted by a loud sputtering noise (the waiting-room door being open.) Looking into the sky, I saw a body passing through the air in a southwesterly direction, inclining downward. It was not round, but in the shape of a banana, turning end on end. It also appeared to be a mass of red-hot composition, from which I could clearly see particles flying. It must have been very large, as I could distinctly see its shape and outline as it turned in the air. It was broad daylight at the time.
"What was it?"
ASTRONOMY AND NUMISMATICS.
Dr. A. VERCOUTRE, in L'Astronomie for September, 1890, points out how astronomical knowledge may be of service to numismatical science. It is known that on many antique medals, and notably on the coins of the Roman Republic, stars and members of the solar system figure sometimes as symbols and sometimes as heraldic allusions to the magistrate by whom the coin was struck. Thus, on a coin struck by L. LUCRETIUS TRIO, 74 B. C. the seven stars in Ursa Major are shown, and this constellation, being named SEPTEM TRIONES, was evidently used as a phonetic allusion to the surname (TRIO) of the magistrate. Again, on a coin struck in B. C. 43, Dr. VERCOUTRE noticed five s'ars, one of which was much larger than the others. He therefore concluded that the constellation represented on the coin was Taurus, as this was the only group of five stars known to the ancients, in which one was more brilliant than the others. On this account he was able to attribute the coin to P. CLODIUS TURRINUS, who apparently used the constellation Taurus or Taurinus as a phonetic signification of his surname. coin struck by MANIUS AQUILLUS, B. C. 94, has figured upon it the first four stars in the constellation Aquila.-From Nature, October 2, 1890.
THE MOTION OF THE SOLAR SYSTEM IN SPACE [BY OSCAR STUMPE]. The Astronomische Nachrichten nos. 2999-3000 contains a very thorough investigation of the motion of the solar system in space, of which a brief analysis will be given here. The principle at the bottom of this investigation is that first worked out by Sir WILLIAM HERSCHEL and depends on the fact that the stars which lie in the region towards which the solar system is moving will, on the whole, seem to separate from each other, while the stars in the region from which the system is moving will, on the whole, seem to crowd together, while, again, the stars on the two sides, as it were, will, on the whole, keep their relative distances. The case is analogous to that of a traveller moving in a straight path through a forest of trees. Those in front of him will seem to separate and those behind will seem to crowd together, owing to appearances caused by his own motion. The trees in a forest are fixed and all the apparent motions are apparent only-parallactic-caused by the movement of the traveller. Each star, however, has a motion of its own-motus peculiaris-as well as a motion due to the displacement of the observer-motus parallacticus.
The first step, then, in an investigation of the sort, is to obtain determinations of the observed stellar motions which are as precise as possible. As the total motion of a star in a hundred years even, is itself a small quantity, it is of the first importance to determine this datum with accuracy. Dr. STUMPE has chosen for consideration all stars whose proper motion in a century is as great as 16". There are 1054 such stars whose positions and proper motions for 1855.0 are given, after having been reduced to the system of NEWCOMB (Washington observations 1870) and Boss (Declination of Fixed Stars 1877). Unfortunately they are not regularly distributed over
the sky and the great majority of them are northern stars. With these materials, the author proceeds to the solution of the problem. Almost all preceding investigations of the sort, of which there have been many, have been carried on under the assumption that the
* Professor Boss pointed out to me in a private letter (which I have his permission to use) that Dr. STUMPE has erroneously assumed that the systems of AUWERS and NEWCOMB- Boss are practically identical for 1755. The difference NEWCOMBAUWERS has been treated by FARQUHAR in the Astronomical JOURNAL NO. 209 (see also A. J. No. 213) and the difference BOSS-AUWEKS in A. J. 196 (see also Proc. A. A. A. S. 1879) It appears that the correction for the Zodiacal Stars necessary to reduce the Fundamental Catalogue of AUWERS to the system of the American Ephemeris is
For R. A.+os.006 + os.ocos (T-1875), and
For Decl.o".22 -0.013 (T-1875) approximately. The Decl, correction varies, however, quite markedly from north to south.