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PRESTON, sent by the Coast and Geodetic Survey Department of the United States, began making latitude observations in Honolulu about the beginning of June, 1891. In a letter from Professor FOERSTER, received a few weeks ago, he tells me that he has already received from Honolulu a first installment of several hundred determinations of latitude, made during the first three months of the proposed year of observations; and that, in comparing these results with the corresponding results of the Berlin Observatory, he finds beyond doubt that in these three months the latitude increased in Berlin by one-third of a second, and decreased in Honolulu by almost exactly the same amount. Thus, we have decisive demonstration that the motion, relatively to the earth, of the earth's instantaneous axis of rotation is the cause of variations of latitude which had been observed in Berlin, Greenwich, and other great observatories, and which could not wholly be attributed to errors of observation. This, Professor FOERSTER remarks, gives observational proof of a dynamical conclusion contained in. my Presidential Address to Section A of the British Association at Glasgow, in 1876, to the effect that irregular movements of the earth's axis to the extent of half a second may be produced by the temporary changes of sea-level due to meteorological causes.

"It is proposed that four permanent stations for regular and continued observations of latitude, at places of approximately equal latitude, and on meridians approximately 90° apart, should be established under the auspices of the International Geodetic Union. The reason for this is that a change in the instantaneous axis of rotation in the direction perpendicular to the meridian of any one place would not alter its latitude, but would alter the latitude of a place 90° from it in longitude, by an amount equal to the angular change of the position of the axis. Thus two stations in meridians differing by 90° would theoretically suffice, by observations of latitude, to determine the changes in the position of the instantaneous axis; but differential results. such as those already obtained between Berlin and Honolulu, differing by approximately 180° in longitude, are necessary for eliminating errors of observation sufficiently to give satisfactory and useful results. It is to be hoped that England, and all other great nations in which science is cultivated, will co-operate with the International Geodetic Union in this important work."

THE UNITED STATES NAVAL OBSERVATORY.

In the last Report of the Superintendent of the U. S. Naval Observatory at Washington (extracts from which were given in these Publications, Vol. III, 1891, page 74), attention was called to the needs of the Institution. The Honorable Secretary of the Navy has given consideration to the subject and his conclusions are stated in the following paragraphs.

[Extract from the Report of the Secretary of the Navy for 1891.]

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'The work on the new Naval Observatory has advanced so far that the transfer from the old to the new site will shortly be undertaken. The failure of the contractors has delayed the work of the new building, now in its final stage, but the government is amply protected, and arrangements are now making under the provisions of the contract by which its early completion may be assured.

"When the transfer and installation of the instruments are completed, the government will be in possession of one of the most admirably equipped observatories in the world. The question of the proper administration of this important charge, representing one of the most important branches of scientific investigation undertaken by the government, is one that demands early attention. The system in existence hitherto, by which the selection of the superintendent has been confined to line officers of the navy, subject like other officers to changes of duty at comparatively short intervals, prevents that continuity of administration which is essential in carrying on the work of a great national observatory. No programme of scientific investigation, especially in the department of astronomy, can be carried out successfully by any institution, if liable to frequent interruptions by a change of its administrative head.

"I therefore recommend the adoption of legislation which shall enable the President to appoint, at a sufficient salary, without restriction from persons either within or outside of the naval service, the ablest and most accomplished astronomer who can be found for the position of superintendent.

"I would also recommend, in view of the era of progress and scientific development upon which the observatory is now entering,

that an advisory council be organized, composed of the superintendent of the observatory and its senior professor, and of three other persons of scientific attainments, whose duty it shall be to consider and report upon new instruments and their proper installation; to draw up, with such changes as may be necessary, from time to time, the programme of scientific work, including observation, reduction and publication, and to make such inspections and reports as may be desirable in regard to the character of the work done by the observatory."

With this official encouragement the Astronomers of the United States have very generally signed the following petition to Congress.*

TO THE CONGRESS OF THE UNITED STATES:

"Your petitioners respectfully call attention to the question of the future administration of the new Naval Observatory, as one entitled to your careful consideration. The buildings for this establishment are now being completed on a scale and at an expense which, we believe, have never been equaled in the case of any national institution devoted to celestial research. The magnitude of the appropriations made by four successive congresses for this purpose clearly expresses the popular will that the astronomical observatory of the nation should be second to none in the value and interest of its work.

"We therefore respectfully set forth the fact that buildings and instruments are not the chief conditions of success. A wellconsidered plan of work, pursued with zeal under competent scientific direction, is absolutely essential. A body of the ablest astronomers, thrown together without adequate guidance, without any problem to solve, and without a concerted plan of work, can no more achieve success than an army can march and fight without a general. All experience shows that the success or failure of a scientific as of a business institution depends upon its directing head.

"By the labors of many generators of investigators, astronomy has now become a science of such extent that those only who make its cultivation the principal business of their lives can keep pace with its progress, and decide how the energies of a corps of astronomers should be directed.

"The proper administration of the observatory now being

* This petition was signed by all the Astronomers of the Lick Observatory.

completed, therefore, requires that its direction should be placed in the hands of a practical astronomer, and we respectfully ask for such legislation as will secure this end."

It is to be hoped that some action in this very important matter will be reached during the present session, and those members of the A. S. P. who are interested can do valuable service by writing to their Senators and Representatives in Congress setting forth the reasons why such action is desirable. E. S. H.

"A METEORIC CRATER.

"FLAGSTAFF (ARIZONA), Nov. 30, 1891. "G. K. GILBERT and MARCUS BAKER, the former being Chief Geologist of the U. S. Geological Survey, have returned from the Cañon Diablo, where they were sent by the Government to make a map of the region where so much meteoric iron has recently been found.

"They spent sixteen days investigating the mammoth hole in the ground supposed to have been made by a meteor. This hole is 625 feet deep and two and one-eighth miles in circumference.

"The theory is, from the appearance of the walls and from the fact that there have been found many pieces of meteoric iron around the hole, that the meteor penetrated the earth to a depth of 700 or 800 feet before it exploded, and this accounts for the strange phenomenon.

"Three pieces of the meteor, weighing 300, 600 and 850 pounds, respectively, were found on the mesa within two miles of the crater and are now in the Smithsonian Institution. Besides these, they found many pieces weighing from two ounces upward.-Telegram to the San Francisco Examiner, Tuesday, December 1, 1891.

A BRIGHT METEOR.

NORDHOFF, Ventura County, CALIFORNIA,
November 21, 1891.

E. S. HOLDEN, LL. D., Mt. Hamilton, Cal.

DEAR SIR: On Wednesday, the 18th inst., at about 10.30 o'clock, P. M., or perhaps a little later, a very strange and unusual phenomenon was noticed by a member of my family and another person, on returning from a concert. A sudden flash of

light, which startled the occupants of the buggy, and frightened the horse attached, was seen moving from southwest to northeast, and then became stationary. The position of persons was in a narrow valley about a mile wide and surrounded by mountains; and this magnificent stream of light (which seemed to eclipse the bright moon-light) appeared to cover from one-fourth to onethird of the horizon. There was a nucleus, at first, which gradually disappeared, after which, at the center of this broad blaze of light there seemed to be a fading away, until a blackish-blue stripe was formed, but the outer edges of the light remained plainly visible for one-half to three-fourths of an hour, or while the horse walked slowly three-quarters of a mile. There was no report as in case of the falling meteoric stone. The parties would be ready to answer any queries you might propound. *

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H. J. DENNISON.

INSTALLATION OF THE NEWALL REFRACTOR AT THE UNIVERSITY OF CAMBRIDGE.

The great telescope presented by Mr. NEWALL to the University of Cambridge, England, was used for the first time at Cambridge early in October, 1891, by Professor J. C. ADAMS, in an examination of the planet Neptune.

It is exactly 46 years since Professor ADAMS, then a student at Cambridge, sent his calculations of its position to the Observatory of Greenwich, and it is 45 years since the actual discovery of the planet at the Observatory of Berlin (September 23, 1846).

DR. RUTHERFURD'S NEGATIVES OF THE MOON.

Through the kindness of Professor REES the Lick Observatory collection of copies of Dr. RUTHERFURD'S moon-negatives has been enriched by three examples additional to those named in the Publications (vol. iii, page 373), as follows:

1864, November 10, Age 11 days.

1864, November 13. Age 14 days (2 copies).

I understand that Professor REES is making a study of the original negatives in New York with special reference to the history of Dr. KLEIN's new crater near Hyginus. E. S. H.

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