NATURE 
| NOVEMBER 20, 1913 
346 
I give drawings representing the corresponding 
parts of these two bones. The determination 
is not difficult; in each bone, enough of the lower 
border is preserved to guide one with certainty to the 
identification of right aad left parts. In both sides 
the lower hinder angle of the parietal bone is broken 
away, but although not fractured in exactly the same 
manner, the lowest point in both cases may be taken 
as in strict correspondence. In this reconstruction 
then the lower border of the right parietal occupies a 
position nearly half an inch higher on the right than 
on the left side. I think that discrepancy must be 
due to an error in reconstruction. 
I have not entered into a discussion on the mark- 
ings which indicate the middle line of the skull for 
this reason. A very considerable experience in attempt- 
ing to reconstruct ancient and modern skulls from 
fragments has convinced me that if a wrong bearing 
is taken—if one misidentifies any point in the middle 
line—unless it be a very slight error, that misidentifi- 
cation will find the reconstructor out, and his taslk 
will be brought to a halt by the development of a 
degree of asymmetry. If, on the other hand, points 
are rightly recognised—often it has to be by repeated 
experiment—then the parts fit easily together, pro- 
vided there is a sufficiency of them, and in the case 
of Piltdown there is an ample sufficiency. I look 
upon the problem of rightly reconstructing a skull 
as similar to that of replacing the fragments of a 
broken vase of symmetrical design. Given the frag- 
ments of the greater part of one half and a part of 
the other, there cannot be two reconstructions. All 
the parts may be got together except one fragment. 
The remaining fragment is evidence that the task has 
not been accomplished. I know very well that my 
friend Prof. Elliot Smith is searching for a true 
representation of the brain-state of the very earliest 
human form that can claim any direct relationship to 
modern men; I hope I may claim the same spirit for 
myself. I also admit that he has gone a considerable 
way towards what, inmy opinion, must have been the 
original form. The points on which we disagree are 
now apparent, and I am content, having had an 
opportunity of presenting my case, to leave the final 
decision to the future. Artuur KEITH. 
Royal College of Surgeons, W.C. 
Work of Natural Forces in Relation te Time. 
In the notice of the “Origin and Antiquity of 
Man" (Nature, October 9), the remark that I have 
‘returned to the manner of thinking which was prevya- 
lent before the days of Lyell"’ calls for some comment. 
It would be nearer correct to say that I have adopted 
the manner of thinking occasioned by the facts which 
have come to light since Lyell’s day, and which may 
be succinctly described as that of regarding nature, 
not as a ‘‘uniformity,’’ but an “evolution."’ Lyell’s 
habit of regarding nature as a progression by infini- 
tesimal steps has been corrected by later observations | 
which reveal, at times certainly, a much more rapid 
rate of progress than he and his followers have been 
wont to admit. Lyell certainly failed to appreciate 
the activity even of the present forces of nature. 
For example, in 1842, after a cursory examination 
of Niagara Falls, he put forth the estimate that their 
recession could not have amounted to more than one 
foot a year, and probably one foot in three years, 
thus making the age of the cataract at least 35,000 
years, and probably 100,000. But at his suggestion 
Dr. John Hall made a trigonometrical survey of the 
front of the falls and set up monuments so that the 
rate could be eventually determined by actual measure- 
ments. After seventy years, surveys show that the 
NO. 2299, VOL. 92| 
falls have receded, during the entire period, at a rat 
of about five feet a year. yt 
Again, Darwin, adopting “Sir Charles Lyell’ 
methods in the first edition of his ‘‘ Origin of Species,” — 
estimated that the erosion of the Wealden deposits in — 
England required the work of 306,662,400 years, which — 
he called ‘‘a mere trifle of geological time.’ But on 
having his attention directed to the activity of sub 
aérial erosive agencies acting over the entire surface — 
at all times, concerning which a great mass of 
evidence had recently been gathered, he confessed in | 
‘a second edition that he had made a rash statement, — 
and in subsequent editions withdrew it entirely. The — 
facts accumulated concerning the activity of present 
eroding forces show that instead of the immense period ~ 
originally assumed by Darwin, the whole removal of — 
the Wealden strata would be accomplished in a few — 
million years. . F- 
But it is in respect to the rapidity of glacial moye- — 
ments that the slow rates assumed by Lyell and his 
followers are pre-eminently misleading. Those whose — 
studies of glaciers have been limited mainly to the — 
Alps, have not readily appreciated the facts concern-_ 
ing the movement of glaciers in North America. For — 
example, it was in 1886 that I made the first extended — 
observations upon the great Muir Glacier in Alaska. — 
This glacier presented a water front one mile in 
width, rising 300 ft. above the water, and descending — 
zoo ft. below the water. From examination of 
various lines of evidence I was able to show that, 
when Vancouver surveyed the region 100 years before, — 
the Muir Glacier with various others coming in to — 
Glacier Bay had united to project the ice twenty miles — 
farther south, with a thickness of two or three — 
thousand feet. The correctness of this inference has 
been abundantly corroborated by subsequent observers. — 
But now comes the confirmatory evidence in the — 
fact that the Muir Glacier has receded seven miles” 
and a half in the twenty-five years that have elapsed 
since my first observations. Moreover, the ablation — 
from the surface has been such as to lower it 700 ft. 
In short, we have here from actual observation in a_ 
glacial field larger than that of the Alps, evidence 
of greater changes in twenty-five years than some of 
those for which Prof. Penck has demanded many ~ 
thousand years. : es 
The word uniformity as applied to the action of — 
natural forces, both in geology and biology, is un- — 
fortunate and misleading. There is, indeed, con- 
tinuity. But this permits varying rates of movement 
according to evolutionary laws, so that, as Huxley — 
observed, all that Darwin had to do to adjust his 
theory to the recent moderate estimates of geological 
timie was to assume a more rapid rate of variation. — 
Neither need the Darwinian be afraid of recognising — 
| paroxysms in nature, since they naturally follow the 
slow accumulations of strain which finally culminate — 
in some sort of fracture or interruption of the ordinary 
| course of events. I am not a pre-Lyellian, but a 
post-Lyellian. G. FREDERICK WRIGHT. 
| Oberlin, Ohio, October 23. = 
The United States Territory of Hawaii. 
Dr. J. Stantey Garpiner, in his appreciative notice 
of ‘** Fauna Hawaiiensis,”’ in Nature of September 25, 
just received, has used a name against which I must 
enter protest. I thought it a possible misprint, b 
it appears several times as Hawaiia. a 
We shall probably have to bear Cook’s name, Sand- 
wich Islands, from our conservative English friends 
for some years longer, although the Hawaiian king- 
dom was independent many years, and never officially 
| used that name, although having diplomatic and com- 
