98 



SCIENCE. 



[Vol. V., No. 104. 



ter months; the high mean temperature of the au- 

 tumn months; the very large rainfall, which came 

 within half an inch of the extraordinary precipita- 

 tion of the year 1876; the unusual percentage of 

 cloudiness; the low velocity of the wind; the decided 

 preponderance of south winds over north winds; and 

 the increased percentage of atmospheric humidity. 



The master of the steamship British King, from 

 Swansea, reports, Jan. 15, in latitude 41° north, lon- 

 gitude 67° 10' west, encountering an electric storm 

 which lasted about four hours. The weather had 

 been overcast with heavy rain from noon until six 

 p.m., when the wind shifted from south-west to west, 

 followed by loud claps of thunder and vivid flashes 

 of lightning. At the same time large balls of 'St. 

 Elmo's fire ' were seen on all the yard-arms and mast- 

 heads. All of the stays and back-stays were covered 

 with sparks of fire of a bluish tint. 



Professor Kiessling of Hamburg has issued a cir- 

 cular in the name of the Hamburg-Altona branch 

 of the German meteorological society, asking prac- 

 tised observers, accustomed to noting the appearance 

 of the sky, for reports on the colors still visible in 

 the neighborhood of the sun in clear weather, as well 

 as for records of the dates on which these peculiar 

 displays first became visible. He regards them as 

 sequels to the extraordinary twilights of 1883, and 

 considers all these optical effects as results of the 

 Krakatoa eruption. The phenomena on which obser- 

 vations are especially desired are the vaguely defined, 

 smoky, reddish ring enclosing a brilliant whitish disk 

 around the sun; and the pale 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 are 

 particularly valuable; and the records of mountain 

 observatories are of greater interest than those of 

 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 Kiessling has 

 published valuable papers on the optical theory of 

 the brown-red ring in the N«turforscher and in Das 

 ivetter. 



In his report on the New-Hampshire state tri- 

 angulation in 1884, Prof. E. T. Quimby says, " It 

 may be proper to mention that while the ' red sun- 

 sets ' have not been so marked as they 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 been 

 no day when the sky has had its normal blue." 



THE CHEMISTRY AND PHYSICS 

 THE SEA. 



OF 



Forchhammer showed in 1864, by his analy- 

 sis of several hundred samples of sea-water, 

 that, though the water of the ocean may vary 



Hejiort of the scientific results of the voyage of IT. M. 8. Chal- 

 lenger during the years 1873-76. Physics and chemistry. 

 Vol. i. London, Government, 18S4. 307 p., 278 pi., map. 4°. 



greatly in degree of dilution, the composition 

 of the saline matter in solution is, for surface- 

 waters, and so far as concerns the chlorides and 

 sulphates of sodium, magnesium, and calcium, 

 — the principal components, — constant within 

 the limits of error of his work. Besides these 

 more important constituents, other substances 

 to the number of twentj'-four elements are 

 known to occur, but in their entire sum amount 

 to but a small fraction of one per 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. Seventy-seven samples, repre- 

 senting different stations upon the ocean, and 

 various depths beneath the surface, yielded 

 figures, which, agreeing fairly well with those 

 of Forchhammer, and better still among them- 

 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, and 

 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 for the mean composition of the salts in 

 sea-water, in comparison with those of Forch- 

 hammer : — 





Per 



hundred 



parts of 



total salts. 



Per hundred of halogen 

 calculated as chlorine. 





Dittmar. 



Dittmar. 



Forchhammer. 



Chlorine 



Bromine 



Sulphuric acid (S0 3 ) . . 

 Carbonic acid (CO.,) . . 

 Lime (CaO) . . ". 

 Magnesia (MgO) . . . 

 Potash (K 4 0) .... 



Soda (Na 2 0) 



(Basic oxygen, equivalent 

 to halogens) .... 



55.2920 

 0.1884 

 0.4100 

 0.1520 

 1.6760 

 6.2090 

 1.3320 



41.2340 



(-12.4930) 



99.8480 

 3402 



11.5760 

 0.2742 

 3 0260 



11.2120 

 2.4050 



74.4620 



Not determined. 

 N"ot determined. 



11.88 



Not determined. 



2.93 



11.03 



1.93 



Not determined. 



Total salts 



100.0000 



180.5840 



181.10 



Or, combining acids and bases arbitrarily, 



Chloride of sodium 77.758 



Chloride of magnesium 10.87S 



Sulphate of magnesium 4.737 



Sulphate of lime 3.600 



Sulphate of potash 2.465 



Bromide of magnesium 0.217 



Carbonate of lime 0.345 



Total salts 100.000 



The difference between surface and interme- 

 diate waters in the contents of lime was 0.01 2.") 



