BAILEY. | Mineral Waters. 27 
stances that originally were present in the waters are found—it 
is possible that the ocean has changed much in composition.’ 
It is easily understood, however, that the great contributions 
to the solid matter of the sea have come from the mineral mat- 
ter dissolved from the streams that are continually carrying 
their burden to the ocean. These streams not only carry im- 
mense quantities of suspended matter which is building the 
great deltas in front of the mouths of the large rivers, but they 
have carried the soluble matter of the rocks and soils over which 
they have passed. On this theory, too, one should expect to 
find all the elements that are found on land in varying propor- 
tions in the sea water. This is practically true, for even such 
an insoluble substance as gold is present in an appreciable 
quantity. Forchhammer’ mentions twenty-seven of the ele- 
ments as found in the sea water, and to these, others such as 
arsenic, lithium, cesium, rubidium and gold should be added. 
Dittmar,‘ in his report on the waters collected in the ‘‘Chal- 
lenger’’ expedition, gives the following as the average composi- 
tion of sea water : 
Uncombined. . Combined. 
Chioring(C))\ tee eee 55.292 | Sodium chlorid (NaCl)....... 77.758 
Broming@Br)ieeee soe oe ae: .188 | Magnesium chlorid (MgCle)... 10.878 
Sulfuric anhydrid (SO3)...... 6.410 | Magnesium sulfate (MgSQO,4).. 4.737 
Carbonic anhydrid (COz)..... .152 | Calcium sulfate (CaSOsz)...... 3.600 
Calcium oxid(CaQO).......... 1.676 | Potassium sulfate (K2SO;4).... 2.465 
Magnesium oxid (MgQ)....... 6.209 | Magnesium bromid (MgBre).. 217 
Potassium oxid (K20)........ 1.332 | Calcium bicarbonate 
Sodium oxid (NasO).......... 41.234 (Cailslo (OOg\boccacsabocco 345 
Less oxygen equivalent....... 12.493 ANA GAT ATE) coum 100 00 
Motalusaltssenn ay eee OOOO 
Other authors state the saline matter in the ocean to be from 
3.47 to 3.51 per cent., and note the fact that inland seas would 
not be so strong where they received large accessions of fresh 
water from rivers, while in some situations bays and shallow 
seas might become more concentrated from excessive evapora- 
tion of water. 
3. Philos. Trans. K. C. I. V., p. 205. 
4. Report of the Voyage of the ‘‘ Challenger,’’ 1884. 
