Al'KIL 21, I910] 



NA TURE 



223 



ly visible on the trunk stream. Here, for a dis- 



^ of nearly fifteen miles above its end, the whole 



ice "is broken into ice hillocks, separated by deep 



essions and heavily coated with debris of every 



from mud and sand to granite blocks 20 to 50 



in diameter," such as may be seen in the gigantic 



er-table, for the picture of which (Fig. i) we are 



jted to the Royal Geographical Society. From 



tlv below the entrance of the Haigatum tribu- 



a band of white ice appears among these hillocks, 



vviiich broadens out as it rises until it occupies all the 



southern side of the glacier. On the northern side 



the hillocks persist for eleven and a half miles farther 



up. They vary in height from about 50 to 230 feet, 



ven more, and sometimes recall drumlins in their 



ir arrangement and form. Beyond these hillocks 



ice, as would be expected, is fairly free from 



is. In the other parts, while the lateral moraines 



large, medial moraines are practically absent. 



>.e surface exhibits some other peculiarities. Over 



-'birds of its area lakelets, occupying ice-basins. 



Hispar and its tributaries, as may be seen in Fig. 2. 

 Intra-glacial moraines, due to the excretion of debris 

 which has been engulfed in large crevasses, may also 

 be observed, as well as the usual structures of nevi 

 and glacier-ice. 



The scenery of this region of snowy peaks and giant 

 glaciers has a general resemblance, though on a 

 grander scale, to that of the .Alps and the Caucasus, 

 and its dominant outlines are indicative of the action 

 of fluviatile rather than of glacial erosion. It is 

 also worth noting that, notwithstanding the trough- 

 like shape of the valley occupied by the Hispar ice- 

 stream, neither the map nor the photographs sug- 

 gest any marked truncation of the spurs past which it 

 moves. Yet here, where several ice-streams are 

 crowded into a comparatively narrow corridor, we 

 might expect to find its rocky wall even undercut by 

 their struggle to force a passage. The Hispar Glacier 

 was one of several on which in 1906 the Geological 

 Survey of India fixed marks in order to study their 

 advance and retreat. It then appeared to be practi- 

 cally stationary, and had thus con- 

 tinued to the time of Dr. Work- 

 man's visit. So, too, had the 

 Yengutsa Glacier, which reaches 

 the valley-floor a little below the end 

 of the Hispar. Yet, about five 

 years prior to 1906, it had rapidly 

 advanced for a distance of nearly 

 two miles. One minor point of in- 

 terest may be mentioned. Grouped 

 spires or pyramids of snow or ice 

 were not seldom observed, resem- 

 bling the nieves penitentes of the 

 Andes, to which Dr. Workman, 

 though not without protest from Sir 

 Martin Conwav, extends the name. 



T. G. BONNEY. 



Fig. 2.— a border-lake near the junction of the Jutmaru with the Hispar Glacier. It i» enclosed by 

 a lateral moraine and the mountain-wall en the ri^ht, and the high side of the Jutmaru Glacier 

 on the left, from which the ice-fragments floating on the water arc de ived. The_ stratification of 

 the blackened glacial ice is well setn. Behind aie the high snow-peaks walling in the Jutmaru. 

 (From the Gci graphical J mt-inal) 



are unusually common. Thus, as might be antici- 

 pated, it is but little crevassed. In. fact, the only ice- 

 fall is at the beginning of the descent from the actual 

 pass, where the subglacial valley floor naturally 

 steepens. In these circumstances the " hum- 

 mocky " surface appears at first sight anomalous, but 

 of this Dr. Workman off'ers a satisfactory explana- 

 tion. The trunk stream of the Hispar receives at 

 least a dozen tributary glaciers, most of them large. 

 The valley, however, is a trench of only moderate 

 breadth, bounded by steep, rocky walls. As the side 

 streams are too strong to be ponded back by the 

 main one, they force their way downwards side by 

 side with it. Thus the pressure becomes greater than 

 the resisting power of the ice, and this is squeezed 

 upwards into ridges and protuberances. These are 

 favourable to the formation of lakelets, which extend 

 up to an elevation of about 16,000 feet, surface streams 

 being correspondingly rare. Other lakelets, formed 

 by dams of ice or moraine, occur at the side of the 

 NO. 21 12, VOL. 83] 



n ALLEY'S COMET. 



SINCE its conjunction with the 

 sun Halley's comet has been 

 seen from several observatories, and 

 on April 16 was seen with the naked- 

 eye by the observers at Cape Town. 

 Thus there is some reason for hop- 

 ing that, given clear morning skies, 

 the comet may become easily observ- 

 able in England, although its low 

 altitude at sunrise, until after it has 

 transitted the sun on May 19, is not 

 favourable. 



The following is part of the 



ephemeris calculated for April and 



Mav bv Dr. Smart, and communicated by Mr. Crom- 



.\s will be seen from the ephemeris, the comet, 

 when near the sun, will travel ven.- quickly across our 

 line of vision, traversing .\ries, Taurus, Orion, and 

 part of Gemini between May 16 and 22. 



