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had been in a great measure removed. Then man advanced as 
the land rose, now bared of ice, and lived along the rivers that 
drained that land, and with him the large mammals associated 
with him in palaeolithic times. Earth-movements still went 
on, and probably still are going on, checking the rate of 
waste in one valley and hurrying it in another, adding another 
element of uncertainty in all our calculations of the date of 
man's appearance. 
The Chairman (J. E. Howard, Esq., F.R.S.). — I may tender the thanks of 
all to Professor Hughes for his very able and interesting paper. Although no 
geologist, it has been necessary for me to acquaint myself, in a measure, 
with some geological facts, having been for nineteen years chairman of a slate- 
quarry in North Wales. I am, therefore, able to confirm what Professor 
Hughes has stated with regard to the features of the country, and I believe, 
as he has been telling us, that there has been an amazing variation in the 
level of that part of the country, with a depression perhaps of 1,500 feet, 
nd subsequent elevation, whilst the amount of disturbance was much less 
on this side of the island. The question of alteration of temperature is 
one that it is clear we have not yet got to the bottom of.' I think I 
am justified in saying we have proofs of a climate in Greenland which 
allowed a growth of vegetation similar to that of the Southern States of 
North America, such as magnolias, &c., that would involve perhaps an 
average of twenty degrees higher temperature than exists now in Greenland. 
I do not believe that any alteration which we can conceive in the elevation 
of the mountains in this part of the world, would cause such a difference of 
temperature. Moreover, I have had in my hands a section for the 
microscope, of a small tree from the extreme north, which seems to imply a 
totally different climate to that which now prevails. The circumstance of 
any possible change of the earth’s axis, will not allow, as Professor Hughes 
has said, of any such alteration of climate as we are considering for Green- 
land. The question is, under what conditions have these changes arisen ? 
Of course we have yet very much to learn. I now ask those more acquainted 
with the subject than I am, to give us the benefit of their knowledge. So 
far as mine extends, it is confirmatory of what Professor Hughes has 
been telling us, with this exception, that I do not think the facts bear out 
the inferences as regards the alteration in the climate. 
Captain F. Petrie. — Before the discussion commences I have to read 
the following letter from Professor W. Boyd Dawkins, F.B.S. : — 
The Owens College, Manchester, March 12th, 1880. 
Dear Sir, — I regret that I am unable to come to your meeting next 
week to support my friend Professor Hughes, on whose essay I have no 
criticism to offer, as I agree with the whole of it.— I am, dear Sir, yours 
truly, W. Boyd Dawkins.” 
