Page:Science vol. 5.djvu/335

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APfKL IT, 1886.1

��tioQ of the new syatem, and afler it. The same sort of difficuUj' now exists id comparing ob- servations made before and after the introduc- tion of the Gregorian calendar; but in this case the discontinuity araounla to ten or eleven daye, and cannot escape notice, while the dis- continuity involved in the proposed system would be only twelve hours, and might easily be overlooked with most damaging conse- qneoces. This objection is undoubtedly valid and weighty. The other objections urged, as to changes needed in the ephemerides, really amount to very little. At present, one has to stop a. moment to consider whether he is act- ing as a civilian or an astronomer when he opens the Kphcmeris to look out data; and it is quite immaterial as regards the numbers given for noon, for instance, whether noon is called Oh. or 13 h. As to the changes in the printing of the Ephemeris, they would involve a little extra work the first year, but nothing of any consequence.

Per contra, a considerable majority of the astronomers consulted by Commodore Frank- lin were of opinion that the advantage gained by abolishing the distinction between civil and astronomical reckoning would fully com- pensate for the admitted annoyance conse- quent upon the change. The number of peo- ple inconvenienced by the change would be very small, and the)' would be persons abun- dantly able to guard against mistakes such as others would be likely to make. On the other hand, the present system leads to conAision in the case of all neophytes in astronomical work: indeed, pretty good astronomers are some- times caught napping when they look into the almanac for forenoon data; and in publishing observations it is often necessary, and alwaj-a wise, to state whether civil or astronomical reckoning is used. Of course, the change in itself considered is of very little importance; but it does seem rather unfortunate that the recomraendatioos of the Washington confer- ence should fail, to begin with, at the Washing- ton observatorj', and the effect will undoubtedly be to postpone the acceptance of the whole system of proposed reforms.

��The general interest in the scientific work of most polar exijeditions has been seriously affected by the long delay which necessarily oc-curs in the publication of the records and results. With the permission and concurrence of Gen. W. B. Hazen, chief signal-officer, I take pleasure in giving, as far as I can at present, a brief summary of some of the scien- tific results of the Lady Franklin Bay expe- dition.

Hourly magnetic declination observations for thirty-two days on which they were made previous to .July 1, 1882, were re<luced at Fort Conger. The mean declination thus obtained was 100° 12' west, being 1° 32' less than the result deduced from the observations of the English exijedition of 1875-7G. The maximum easterly deflection occurred at 2 a.m., local time {7 a.m., Gottingen mean time), and the maximum westerly deflection at 12 m. A primarj- maximum at 4 p.m., most probably was due to disturbances. These deflections arc from one to two hours later than those ob- tained froiu the obser^-ations of Lieuts. Archer and Fulford, B.N.. in 1875-76; but it is pos- sible that the observations for the complete year, which are now in the hands of Assist- ant Charles Schott of the U. .'^. coast and geodetic survey for reduction, may give other results. The hours, however, agree with those determined for Van Rensselaer harbor by Mr. Schott, in the discussion of Kane's observa- tions. The absolute range of the English observations was 8°; and the greatest daily change, 5° 9.4'. From 8.35 a.m. (Gottingen mean lime), Nov. Ifi. 1883, to 10.30 p.m., Nov. 18, the absolute range as observed was 20° 28.2'. — from 113" 19.8' west, to 92° 51.6' west. These times and figures arc given as of more than common interest in connection with the great magnetic storm of November, 1883. The changes at Conger were much greater, it will be observed, than at Godthaab. Greenland, where, Paulsen says, on Nov. 17, 1883, from 2 a.m. until noon, the declination bad varied 4° 44' to the east, and later about 5° to the west: so that the variations for the day reached 9.5°.

The following table of monthly means has

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