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TSAIDAM—TSANA
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donovani, Lav. et Mesn.) parasite d'une fièvre de l'Inde,” C. r. ca. sci. (1903), 137, p. 957, figs.; (28) idem, “Sur la nature bactérienne du prétendu trypanosome des huitres, T. balbianii,” C. r. soc. biol. (1901), 53, p. 883; (there are numerous other papers by these authors in the C. r. ac. sci. and the C. r. soc. biol. from 1900 onwards); (29) L. Léger, “Sur un flagellé parasite de l'Anopheles maculipennis,” C. r. soc. biol. (1902), 54, p. 354, figs.; (30) idem, “Sur la morphologie du trypanoplasma des vairons,” C. r. ac. sci. (1904), 138, p. 824; (31) idem, “Sur la structure et les affinités des trypanoplasmes” (1904), t. c. p. 856, figs.; (32) idem, “Sur les hémorflagellés du Cobitis barbatula, L. I. Trypanosoma barbatulae, n. sp.,” C. r. soc. biol. (1904), 57, p. 343; (33) idem, “Trypanoplasma varium, n. sp., parasite du sang de Cobitis barbatula, L.” (1904), t. c. p. 345; (34) idem, “Sur les affinités de l'Herpetomonas subulata et la phylogénie des trypanosomes” (1904), t. c. p. 615; (35) idem, “Sur la présence d'un trypanoplasma intestinal chez les poissons,” op. cit. (1905), 58, p. 511; (36) W. Leishman, “On the possibility of the occurrence of trypanosomiasis in India,” Brit. Med. Journ. (1903), i. 1252, figs.; (37) idem, “Note on the nature of the parasitic bodies found in tropical splenomegaly,” op. cit. (1904), i. 303; (38) Leishman and Statham, “The development of the Leishman body in cultivation,” Journ. Army Med. Corps (1905), 3, 14 pp., 1 pl.; (39) J. Lignières, “Contribution a l'étude de la trypanosomose des équidés sud-americains connue sous le nom de Mal de Caderas,” Rec. med. vet. (8) (1903), 10, p. 51, 2 pls.; (40) A. F. Mayer, “Spicilegium observationum anatomicarum de organo electric in raiis anelectrias et de haematozois,” (Bonn, 1873), 18, pp., pls.; (41) F. Mesnil, F. Nicolle and P. Remlinger, “Sur le protozoaire du bouton d'Alep,” C. r. soc. biol. (1904), 57, p. 167; (41a) E. A. Minchin, “On the occurrence of encystation in Trypanosoma grayi,” &c., Proc. Roy. Soc. (1907), 79 B, p. 35.; (41b) idem (with Gray and Tulloch), “Glossina palpalis in relation to Trypanosoma gambiense,” &c., op. cit. (1906), 78 B, p. 242, 3 pls.; (42) Mitrophanow, “Beiträge zur Kenntniss der Hämatozen,” Biol. Centbl. (1883), 3, p. 35, figs.; (43) G. Nepveu, “Sur un trypanosome dans le sang de l'homme,” C. r. soc. biol. (1898), 50, p. 1172; (44) F. G. Novy and W. J. McNeal, “On the Trypanosomes of Birds,” Journ. Inf. Dis. (1905), 2, p. 256, pls.; (45) W. S. Perrin, “The life-history of Trypanosoma balbianii,” Proc. Roy. Soc. (1905), 76 B, p. 367, figs., also in Arch. Protistenk. (1906), 7 pls.; (46) M. Plehn, “Trypanoplasma cyprini, n. sp.,” Arch. Protistenk. (1903), 2, p. 175, 1 pl.; (47) S. Prowazek, “Studien über Säugethiertrypanosomen,” Arb. kais. Gesundheitsamte (1905), 22, 44 pp., pls.; (48) L. Rogers, “On the development of flagellated organisms (Trypanosomes) from the spleen Protozoic parasites of cachexial fevers and Kala-azar,” Quart. Journ. Mic. Sci. (1904), 48, p. 367, 1 pl.; (49) R. Ross, “Notes on the bodies recently described by Leishman and Donovan,” Brit. Med. Journ. (1903), i. 1261, 1401, figs.; (50) F. Schaudinn, “Generations- und Wirthswechsel bei Trypanosoma und Spirochaete,” Arb. kais. Gesundheitsamte (1904), 20, p. 387, figs.; (51) idem, “Zur Kenntniss der Spirochaete pallida,” Deutsch. med. Wochenschr. (1905), No. 42, p. 1665; (52) Schaudinn and E. Hoffmann, “Vorläufiger Bericht über das Vorkommen von Spirochaeten in syphilitischen Krankheitsproducten,” Arb. kais. Gesundheitsamte (1905), 22, p. 527; (53) E. and E. Sergent, “Sur un trypanosome nouveau parasite de la grenouille verte,” C. r. soc. biol. (1904), 56, p. 123, fig.; (54) idem, “Hémamibes des oiseaux et moustiques ‘Generations alternantes,’ de Schaudinn,” op. cit. (1905), 58, p. 57; (54a) F. Stuhlmann, “Beiträge zur Kenntniss der Tsetsefliege,” &c., Arb. kais. Gesundheitsamte (1907), 26, p. 83, 4 pls; (55) Valentin, “Über ein Entozoon im Blute von Salmo fario, Muller's Arch., 41, p. 435; (56) O. Voges, “Mal de Caderas,” Zeitschr. Hyg. (1902), 39, p. 323, 1 pl.; (57) Wasielewsky and G. Senn, “Beiträge zur Kenntniss der Flagellaten des Rattenblutes,” op. cit. (1900), 33, p. 444, pls. (58); J. H. Wright, “Protozoa in a case of tropical ulcer (Delhi sore),” Journ. Med. Research, Boston (1903), 10, p. 472, pls.  (H. M. Wo.) 

TSAIDAM, or more correctly Tsädum, a depression, or self-contained shallow basin in the N.E. of Tibet, crossed by 37° N. and stretching from 92° to 97°. It is separated from the high plateau of Tibet by the Burkhan-Buddha range, and on the N.E. it is bounded by the eastward continuation of the Astintagh ranges, which there consist of four, namely, the lower and upper ranges, and a subsidiary chain flanking the lower range on the north and another subsidiary chain flanking the upper range on the south (see Kuen-Lun).

The valleys which divide the east ranges of the Kuen-Lun system terminate, or rather merge in, the sandy desert basin of Tsaidam; amongst them the Kakir valley between the upper Astin-tagh and the Akato-tagh and the Kum-kol valley between the Kalta-alagan and the range I. of the Arka-tagh (see Kuen-Lun). Tsaidam lies at an altitude of 11,400 ft. or about 3000 ft. lower than the Kumkol lakes, and receives from the valley in which they lie the river Chulak-akkan or Tsagan tokhoy, which rises probably on the north slope of the Shapka-monomakha Mountain, one of the culminating summits in the region north of the Arka-tagh range. “It is very possible that the north-west of Tsaidam, which is perfectly unknown, is broken up into several separate basins. The south-east part of the same great expanse also appears to consist of several smaller basins rather than of one single great basin, each possessing its own salt lake; but then these smaller basins are undoubtedly separated from one another by remarkably low and insignificant thresholds or swellings.”[1] The north-east part of the basin consists of a network of basins, which admit of being grouped in four divisions—Särtäng or Serteng, Makhai, Tsädam or Tsaidam, and Kurlyk or Tosun. The characteristic feature of each of these is that which is found in so many of the valleys of the Tibetan borderland, namely, a pair of linked lakes, one containing salt water and the other fresh water. The only inhabitants of Tsaidam are Mongols—Särtang Mongols in the north and Tajinur Mongols in the south. The south-east part of the region is drained by the Holuzun-nor or Baïn-gol, an affluent of the upper Hwang-ho or Yellow River of China. The Särtäng basin is drained by the Khalting-gol and its tributary the Holuin-gol, which rise in the Humboldt and Ritter Mountains and empty into the lake of Sukhain-nor.

TSANA, a lake of North-East Africa, chief reservoir of the Abai or Blue Nile. Tsana lies between 11° 36′ and 12° 16′ N. and 37° 2′ and 37° 40′ E., filling a central depression in the Abyssinian highlands. It is about 5690 ft. above the sea, but from 2500 to 3000 ft. below the mountain plateau which encircles it. Its greatest length is 47 m., its greatest breadth 44 m., and it covers, approximately 1100 sq. m., having a drainage area, including the lake surface, of some 5400 sq. m. In shape it may be compared to a pear, the stem being represented by the escaping waters of the Abai. The shores of the lake are well defined, generally flat, and bordered by reeds, but at places the mountains descend somewhat abruptly into the water. Elsewhere the land rises in gentle undulations, except at the mouths of the larger tributary streams, where are alluvial plains of considerable size. At the south-east end the lake forms a bay about eleven miles long, and from three to eight miles across, and from this bay the Abai issues. The whole of the coast-line is considerably indented and many narrow promontories jut into the lake. The island of Dek (8 m. long by 4 broad) is in the south-western part of the lake. Near it is the smaller island of Dega, whilst numerous islets fringe the shores.

Lake Tsana is fed by three large rivers and by many petty streams. The chief tributary is the Abai, which enters the lake at its south-west corner through a large papyrus swamp. This river, and the Abai or Blue Nile which issues from the lake, are regarded as one and the same stream and a current is observable from the inlet to the outlet. Next in importance of the affluents are the Reb and Gumara, which run in parallel courses and enter the lake on its eastern side. The outlet of the lake is marked by openings in a rocky ledge, through which the water pours into a lagoon-like expanse. Thence it issues by two or three channels, with a fall of about 5 ft. in a succession of rapids. These channels unite within a couple of miles into one river—the Abai with a width of 650 ft. After passing a large number of rapids in the first sixteen miles of its course the Abai enters a deep gorge by a magnificent fall—the Fall of Tis Esat—the water being confined in a channel not more than 20 ft. across and falling 150 ft. in a single leap. The gorge is spanned by a stone bridge built in the 17th century. From this point the Abai makes its way through the mountains to the plains of Sennar, as described in the article Nile.

The average annual rainfall|Rain in the Tsana catchment area is estimated at 33 ft., and the volume of water received by the lake yearly at 6,572,000,000 of cubic metres. More than half of this amount is lost by evaporation, the amount discharged into the river being placed at 2,924,000,000 cubic metres. The seasonal alteration of the lake level is not more than 5 ft. The rainy season lasts from the beginning of June to the end of September. During this period the discharge from the lake is, it appears, little greater than in the dry season, the additional water received going to raise the lake level. Thus the rise in the Blue Nile, in its lower course, would seem to be independent of the supply it derives from its source.

Tsana has been identified with the Coloe Palus of the ancients, which although placed 12° too far south by Ptolemy was described by him as a chief reservoir of the Egyptian Nile and the source of the Astapos, which was certainly the Blue Nile. In 1625 it was visited by the Portuguese priest Jeronimo Lobo, and in 1771 by James Bruce. Dr. Anton Stecker, in 1881, made a detailed examination of the lake, enabling the cartographers to delineate it with substantial accuracy. By the Portuguese of the 17th century the lake was styled Dambia,

  1. Sven Hedin, Scientific Results of a Journey in Central Asia, 1899–1902, iii. 344 (Stockholm, 1905–1907).