21 6 REPORTS ON INVESTIGATIONS AND PROJECTS. 



Altitudes. — The altitude of the Belgian Railway station west of the 

 Ch'ien-mon is 45 meters, or 147 feet, above sea, according to official 

 records furnished by M. Jadot, director of the railway. The Amer- 

 ican Legation site, near by, is a trifle higher, its altitude being about 

 155 feet above sea. By the same authority the altitude of the railway 

 bridge over the Hun River at Lu-k'ou-kiau is stated at 66 meters, or 

 215 feet. The height of the bridge above the river being about 15 

 feet at low water, the river is in round numbers 50 feet above Peking. 



The available figures for the relative elevations of Peking and the 

 Pei River are based on readings of two aneroid barometers, one being 

 read at Peking, the other being carried to Tung-chou and read there 

 as well as at Peking. It appears that Peking is 60 feet, more or less, 

 above the plain of the Pei at Tung-chou. 



The altitudes of mountains immediately surrounding the Bay of 

 Peking, as determined by the Intelligence Branch of the British 

 North China Command, range from 1,500 to 4,200 feet above sea. 

 The mountains are very sharply sculptured, are exceedingly steep, 

 and descend without notable foothills to the plain. Their rocky 

 slopes continue beneath the alluvium of the plain. Spurs extend 

 out into the plain like promontories into a sea, and isolated hills 

 rise like islands through the deposits in which their bases are buried. 



THE PLAIN OF PEKING. 



Surf ace features . — To the unaided eye the Plain of Peking appears 

 to be a monotonous level, in which artificial elevations are conspicu- 

 ous because natural ones are wanting. Instrumental observations 

 show that there are considerable differences of level between widely 

 separated points, but the slope by which they are connected is so 

 slight as to be inappreciable. Streams in their natural channels are 

 rarely sunk a yard below the surface of the plain, which frequently 

 descends slightly in a direction away from their immediate banks. 



Hills which rise above the plain are of three classes — those which 

 are the tops of partly buried mountains, those which are dunes of 

 drifting sand, and those which are artificial. Among the latter is to 

 be classed the so-called Coal Hill, in the Imperial City, according to 

 the testimony of the most reliable observers. 



The level of the plain extends, with remarkable uniformity, almost 

 and sometimes quite to the base of the mountains, but wherever a 

 ravine or valley opens onto it the surface is raised by deposits of 

 gravel and sand from the mountain stream. These deposits consti- 

 tute an alluvial cone, as it is called, which merges into the general 

 imperceptible slope of the plain. Where many small ravines lie near 

 together, their alluvial cones become continuous and constitute a belt. 



