MaxxeeinCt. — On the Miirchison Glacier. 365 



body of ice will flow more quickly thau a lesser — au axiom 

 which holds good with water. The simile is a favourite oue 

 of Tyndall's, Geikie's, aud Forbes's, but is of very ancient 

 origin amongst glacier writers. 



The altitude of the Hooker Glacier at its head is 8,580ft. ;, 

 at its terminal face, 2,882ft. ; length, seven miles; and width, 

 nearly one mile ; and its average descent per mile, 665ft. 

 Mr. Brodrick has endeavom-ed to obtain some idea of the rate 

 of its progress at a point neai" the terminal face, and his 

 observations give an average summer rate of 4-33iu. a day. 

 Allowing for the retarded winter motion, the result for the 

 year would probably be brought down to under 4in. a day. 



The altitude of the head of the Murchison would probably 

 be 6,500ft., though the ridges on either hand are something 

 like 8,000ft., and its terminal 3,600ft. ; its length, say, is foiu-- 

 teen miles, and width a mile to a mile and a half ; and the 

 average descent per mile, 207ft. Assuming Mr. Brodrick's 

 measm-ements of the Hooker to be correct, if we took the 

 Mm-chison by comparison we should probably arrive at a much 

 slower rate of progi-ess. But, of coui'se, tbis is little better 

 than guesswork, for we cannot, except at the terminals of 

 these glaciers, form any sound estimate as to their depth. 

 Only in some places, where their lateral parts are laid bare 

 whilst passing a gorge in the mountains at their sides, or b}' 

 measuring the depth of their crevasses, can we hope to glean 

 some insight into the question. 



By the former method I have attempted in a rough way 

 to arrive at a conclusion regarding the depth of the Tasman 

 Glacier at a point some ten miles from the terminal face, 

 where a large section of the ice is laid bare, showing in a most 

 intevcoting manner a stratification of the ice, and the dis- 

 tortion it has undergone during its downward journey. On 

 the surface of the glacier at this point the aneroid gave a read- 

 ing of 4,500ft., and at the foot of the exposed ice of 4, 000ft., and 

 here was formed an ice-cave by the entrance of a mountain- 

 torrent at a steep angle of descent from the slope of Mount 

 Chudleigh, in the Malte Brun Range. One could penetrate 

 downwards into the cave for a short distance onl}-, owing to 

 darkness, danger from falhng ice, and fi-om the impetuous 

 nature of the torrent ; but it is reasonable to estimate, from 

 what observations I could make, that another 100ft. of thick- 

 ness could be attributed to the ice, making 600ft. for certain. 

 Now, the outlet of the river is 2,450ft. above sea-level, and the 

 surface of the glacier at the point in question 4,500it. ; therefore 

 the ice could not exceed in thickness the difference between 

 these figures, or 2,050ft. But we must consider the slope of 

 the glacier-bed. That of the surface of the glacier inclines on 

 the average from the terminal face (250ft. above the outlet of 



