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Show 190 Humboldt relates that, in Mexico, the dried larvae of an insect from the lake Tescuoo, form an article of commerce among the Indian population of the province. Notwithstanding the alkalinity of Owens Lake, numerous ducks are occasionally seen swimming on it. The great numbers of dead ducks and other aquatic birds seeo here and there on shore seem to indicate that they tried to satisfy their thirst with this water. In regard to the fly- species, an interesting letter from Baron Osten- Saken may be referred to here, to whom were sent a few specimens for examination. He says: " They belong to the genus Ephydra, but differ in some respects from the usual type of the genus. Usually, Ephydra are of a metallic blackish- green, while the species in question is dead gray, and not metallic at all. Other differences may be revealed on a more careful examination. Several species of Ephydra have been observed to live in the larva state in salt water, either in the brackish waters near the shore, or in the brine of salt- works. A species of Ephydra occurs in enormous numbers on the shore of the Great Salt Lake, Utah. I am pretty sure that it is a species different from yours; next summer I hope to ascertain the fact positively." I had suspected the peculiar ale ® of Owen's Lake a new species, and sent a specimen to Professor Wood in Philadelphia for examination; unfortunately, however, I was not favored with an answer. The lake was evidently at one time much larger than at present, and its waters pore and fresh, so as to permit the life of various fresh- water mollusks, as indicated by numerous shells of recent species found in the sand of the vicinity. 4 Upturned strata of limestone and slate, containing numerous dikes of intrusive rock, as diorite and porphyry, skirt the valley of the lake on the east side, while the main mass of the opposite Sierra Nevada consists of granite and gneiss. The taste of the water reveals at once the presence of carbonate of soda. The specific gravity is 1.051. In 100 liters ( = 26.42 gallons) are contained : Grams. Potassium sulphate 644.87 Sodium sulphate 929.1* 7 Sodium carbonate 2,440.80 Sodium chloride 2,328.30 Silicic acid : 17.21 Boric acid traces. Phosphoric acid traces. Nitric acid traces. Lithiat ....•- traces. Lime traces. Magnesia traces. Aluminia traces. Organic matter traces. 6,360.25 The proportion of saline substances is therefore over double as large as in sea- water' and about one- third of that of the Great Salt Lake. But while these contain chloride of sodium, the former contains a large amount of carbonate of soda. To undertake to calculate this for the whole lake is to appreciate its value. The greatest length is 17 miles; width, 9 miles; depth, 51 feet. The total surface of the lake is very closely 110 square miles = 284.9 square kilometers, the average depth 3 meters = 9 feet 10 inches. The cubical contents are therefore = 0.8547 cubic kilometers. One cubic kilometer = 1,000 X 1,000 X 1,000 oublc meters. * One cubic meter = 1,000 liters. Hence the volume of the lake = 854,700,000,000 liters or= 8,547,000,000 hectoliters. As the analysis shows, one hectoliter contains 2.44 kilograms carbonate of soda, hence the total amount in the lake = 20,854,680,000 kilograms, or 22,000,000 tons.* Evaporation and concentration works might be erected at a moderate cost, and the carbonate of soda separated by crystallization from the remainder of the salts. If by this process also the considerable amount of potassa, which is a valuable fertilizer, were separated and savefl, the outlay for fuel might be compensated. Wood is scarce in the vicinity, and transportation at present expensive, which would be modified with the completion of the projected Independence Railroad. The analysis showed that there is one- twentieth more carbonic acid than required to form with the available soda the xnonocarbonate; hence there is a small amount of bicarbonate present, which, however, was calculated in the analysis as monocarbonate. The amount of bicarbonate formed depends upon the quality and tension of the carbonic acid coming in contact with the monocarbonate, also upon the quantity of water. Another fact to be men- * I find this fact also mentioned by G. K. Gilbert, vol. Ill, Survey Reports. t Careful search was made for traces of rubidium and caesium, according to the method of Bunsen, but no trace was revealed by the spectroscope. t The amount of sulphate of potassa would be 5,000,000 tons. |
