Maech 3, 1907] 



SCIENCE 



395 



of the region, and southeast of (Lake) Issik- 

 kul, where the Syrt is well developed. In his 

 ' Forschungsreise in den zentralen Tien-schan 

 und Dsungarischen Ala-tau' (a work of 311 

 pages constituting volume XX., MUt. Geogr. 

 Qesellsch. Hamburg, 1904; see pp. 87, 91, 

 121), he describes several gently rolling, grass- 

 covered highlands, the flatness of which sur- 

 prised him; but he gives no explicit explana- 

 tion of their origin other than referring them 

 to an ' apparently long period of continental 

 development ' (p. 15Y) without specifying the 

 conditions which subsequently brought about 

 their deep dissection. Similar surfaces of 

 degradation, now slanting at such inclination 



FlQ. 1. The Ishigart range in the Tian Shan, 

 from photograph by Friederichsen (Pet. Mitt., 

 1906, Heft III.). 



as to be sharply dissected by narrow valleys, 

 are described (pp. 198, 206) by the same au- 

 thor in various mountains — or blocks, as one 

 might say — of the Ala-tau, the northern out- 

 lying members of the' Tian Shan system, but 

 again without explicitly explaining why the 

 earlier process of even degradation had been 

 followed by sharp dissection (p. 216). In an- 

 other article (' Beitrage zur Morphologie des 

 centralen Tien-Schan,' Verh. XIV., Deut. 

 Geogr'tages, 1903, 35-42) Friedrichsen briefly 

 considers the possibility of dislocation of the 

 degraded surfaces, preliminary to their dis- 

 section. 



In 1903, E. Huntington crossed the Tian 

 Shan from Issik-kul to Kashgar, and de- 

 scribed the highlands as parts of an uplifted 

 and partly dissected fieneplain ('A Geologic 

 and Physiographic Eeconnaissance in Central 

 Turkestan,' in Pumpelly's 'Explorations in 

 Turkestan,' Carnegie Inst., pub. No. 26, 1905, 

 159-216; see pp. 167, 171), an opinion in 

 which the undersigned fully concurred ('A 

 Journey Across Turkestan,' Ihid., 23-119; see 

 p. 73; also 'A flat-topped range in the Tian 



Shan,' Appalachia, X., 1904, 277-284). Parte 

 of the same peneplain were believed to be 

 recognizable in the even back-slope of several 

 isolated ranges near Issik-kul, which were ex- 

 plained as tilted fault-blocks; and again 

 farther north in the still low-lying Siberian 

 steppe, degraded to small relief on crystalline 

 and deformed stratified rocks in the neighbor- 

 hood of Semipalatinsk. W. M. D. 



MERZBACHER's tian SHAN EXPEDITION 



A MUCH more detailed exploration of the 

 Tian Shan, especially around Khan Tengri, 

 was carried on by Merzbacher's expedition in 

 1902-3, of which the fuller reports are now 

 publishing; but neither in his preliminary 

 report {Pet. Mitt. Erganzlift, 149, 1904; also 

 ' The Central Tian Shan Mountains,' London 

 and New York, 1905) nor in a recent descrip- 

 tive article (' Der Tian-Schan oder das Him- 

 melsgebirge,' Zft. D. und 0. Alpenver., 

 XXXVIL, 1906, 121-151; excellent photo- 

 graphs) does this explorer give particular ac- 

 count of the Syrt, not even to the remarkable 

 slanting table-top of Mt. Catherine (Eig. 2) ; 

 his attention being chiefly directed to the 

 grand massif of Khan Tengri and its great 

 system of radiating glaciers. However, his 

 geologist, H. Keidel, in a report on the scien- 



FiG. 2. Mt. Catherine (about 19,500 ft.), from 

 photograph by Merzbaoher, taken on Ak-bel Pla- 

 teau (13,000 ft), Tian Shan (The Centr. T. S. 

 Mtns., plate opp. p. 177). 



tific results of the expedition (' Geol. IJber- 

 sicht iiber den Bau des zentralen Tian-Schan,' 

 Abh. k. Bayer. Ahad. Wiss., IL Kl., XXm., 

 1906, 91-192), makes it clear that the high- 

 lands of the Syrt, with their astonishing even- 

 ness of surface, are the result of Mesozoic 

 (and early Tertiary ?) degradation of a pre- 



