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other observers, were uot found in the Eostock experiments. On the 

 other hand, however, meteorological phenomena appeared to exercise 

 an undoubted influence. Thus, a snow-fall was frequently connected' 

 with a constantly increased percentage; while rain produced a pre- 

 cisely opposite effect. These influences are not constant; indeed, with 

 snow there was sometimes found a less degree of acid, and with rain a 

 greater. The direction of the wind, however, exercised a constantly 

 api^reciable influence. With atmospheric currents from the northeast, 

 the carbonic acid was increased while with a southwest wind it was 

 diminished. This fact led Professor Schultz to the impression that the 

 sea was a constant absorbent of carbonic acid from the atmosphere, and 

 that the average percentage was kept up by volcanic exhalations, ani- 

 mal respiration, processes of decomposition and combustion, and other 

 causes developed on the laud. Professor Schultz is now engaged in 

 endeavoring to learn to what the absorptive power of sea- water is due, 

 and has already ascertained that sea- water, when boiled, absorbs scarcely 

 one-fourth part as much carbonic acid as sea-water which has lost its 

 carbonic acid by the action of hydrogen. 



Effect of drainage and sewage on mortality in Calcutta. — 

 The extent to which disease depends upon drainage and sewage may be 

 gathered from the report of the results of sanitary improvements in 

 Calcutta. In that i)ortiou of the city inhabited by the native popula- 

 tion, the cholera fatality for twenty years prior to 18G1 averaged nearly 

 5,000 deaths per annum. In 1860, the deaths were G,000 by cholera; 

 and in 1866, nearly 7,000. About this time works of drainage and 

 water supply were commenced, and have been gradually extended ; and 

 as a result, the use of foul tank and river water was discontinued; this 

 benefit being conferred upon the city in the beginning of 1870. As the 

 first result of this action, which is confined to a limited portion of the 

 city, the mortality from cholera in 1870 was only 1,563, the general mor- 

 tality also diminish! ug year by year with the extension of the works. 

 The entire death-rate in 1870 was only 23 in 1,000 — considerably less 

 than half v\'hat it was in 1865. 



Phosphate eeds on the Dniester. — The immense deposits of min- 

 eral phosphates in South Carolina bid fair to be matched by those lately 

 discovered on the banks of the Dniester, in Eastern Europe. From a 

 report of an investigation by Schvrackhofer, ordered by the Austrian 

 government, we learn that these phosphatic concretions differ from 

 those hitherto observed, in being almost entirely globular, with con- 

 centric radiated joints in their interior, and varying in diameter from 

 half an inch to eight inches. When powdered and heated, in the dark, 

 a bluish, iibosphorescent light is observed. The region in which the 

 phosphorite balls occur is characterized by the existence of Silurian 

 and cretaceous strata, all intermediate formations being wanting. The 

 Silurian strata are principally represented by limestone and clay slate, 

 and the latter is either coarsely granulated and compact, or in smooth, 

 lustrous sheets. It is in the latter alone that the phosphatic balls oc- 

 cur, and, indeed, only where this slate is immediately covered by the 

 chalk-marl. From these considerations, it is inferred that the balls con- 

 sisted originally of carbonate of lime, which have been transformed into 

 phosphorite by the infiltration of i)hosphatic salts. The original mate- 

 rial of these chalk concretions was doubtless supplied by the chalk-marl 

 overlying the slate in a manner familiar to geologists, and it may fairly 

 be presumed that the phosphoric acid of the mineral is simply the pro- 

 duct of leaching out of the phosphatic slate above referred to, since all 



