Page:Science vol. 5.djvu/112

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��(T innnlli-i; 1 he high meitii Icinperatiire of the au- luiun m'liilhs; the very largt^ rainfall, nhkli cams within half an inch of the extraordinaiy preciplts- lion lit Ilie year 1BT6; the unusual percentage of oioutlineM; the low velorlty ot the wind; the derided Iireponderance of aoutli wtiida ovi!r north winds; atid the Increased percentage ol atmospheric humidity.

The master of the steamehip British King, from Swansea, reporlB, Jan. 16, in latitude 41° north, lon- gitude 87° 10' west, encountering an electric slonn whirh lasted about four hours. The vreather had been overcast with heavy rain from noon until six P.M.. when the wind shifted from south-weat to west, followed br loud claps of thunder anil vivid flaslies of lightning. At the same time large balls of 'St. Elmo'sBre* were seen on all the yard-arms and mast- heads. All of the slays and back-stays were covei'ed with sparks of fire of a bluish tint.

Professor Kiessling of Hamburg has issued a cir- ctilnr In the name of the Ilamburg-Altona branch of the Oennan raateorologicai society, asking prac- tised obsen'ers, accustomed to noting the appearance of the sky, for reports on the colors still visible in tlip neighborhood ot the sun In clear weather, as well as for records of the dates on which these peculiar displays flrst became visible. He regards them as sequels to the extraordinary twilights of 18S:>, and considers all these optical effects as results of the Krakatoa eruption. The phenomena on which obser- vations are especiaity desired are the vaguely deBned, smoky, reddish ring enclosing a brilliant whitish disk around the sun; and the pole red tint that has been seen between clouds at a greater distance from the sun, while the solar disk itself was hidden. Obser- vations from distant, out-of-the-way stations arp particularly valuable; and the records of mountain ubeetvaiories are of greater interest than those ot lower levels, as the solar diffraction ring is much more distinct when seen in the relatively clean upper air than when viewed through the dust-laden strata Of the lower atmosphere. Professor Kiessliilg has published valuable papers on the optical theory of the brown-red ring In the Nalar/araelier and in Dan

In his report on the New-Hampiblre state tri- an^iulation in 1884, Prof. E. T. Quimby says. " It may be praper to mention that while the ' red sun- sett' have not been no marked as (hey were a year ago, the Krakatoa dust has been constantly and plainly visible from sunrise to sunset every day when the sky has been free from clouds. There has Ih^cii nn day wheji the sky has had its normal blue."

��FdifHHAMMEii showed ill 1NC4, by his iinaly- B\H of several hundreci samples or sea-water, that, tboiigh llic water ol' the oeeaii muy vary

��greatly in degitc of diliilloii, the c-ompositinit of the saline matter in solution is, foi- sDrfacc- waters, and so far as (.■onccrns the clilorides and siitphatcs of sodium, magneaiiiiu, and calcium, — the priiieipal oomijonouis, — constant whhiD the limits of error of his work. Besides these more important conslitneiils, other substancea to the number of twenty-four elements are known to occur, but in their entire sum amount to but u small fraction of one |)er cent of the total saline matter.

In part i. of the volume before us. Professor William Dittmar gives his researches into the composition of ocean-waters collected by the Challenger. .Seven ty-seven samples, repre- senting different stations upon the ocean, and various depths beceatli the surface, vielded figures, which, agreeing fairly well with those of Forchhammer, and better still among llicm- selves, seem to warrant the conclusion that the composition of the salts in sea-water is independent of the latitude and longitude of the station from which the water is taken, aod of depth also, so far as concerns the chlorine, sulphuric acid, magnesia, potash, soda, and bromine. The proportion of lime, however, increases with the depth of the water. The following table contains Professor Dittmar's figures fur the mean composition of the salts in sea-water, in comparison with those of Forch- hammer ; —

�� �P,r

�uticuliHud u ohlortac.

� �D.,.™..,.

�mttinar. IBi-SlSU

� �SolphurleaeWtBO,) ..

�1

�list Nol detirmlniid.

ii!in

���Or, combining acids and bases arbitrarilji

Chloride of sodium 77.788

Chloride of ningnt^ium I0.B7S

Sulphate ofmagiipsium 4.737

Sulphate of lime aOOO

.Sulphate of potash 2.<«6

Bromide of magnesiuni 0.217

Carbonale of lime. 0.845

Total salts lOO.OOn

The diPferem-e lK.>lwcen snrrncc and inlerinf diiile waters in ihc contents of lime was 0.01 :.'

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