Do 
amongst the stars should be noted at short intervals. 
In the case of a streak enduring ten minutes, a series 
of diagrams showing the positions -of the streak and 
neighbouring stars every two minutes would be valu- 
able. 
There is a-large amount of data available from past 
observations, but it is for the most part of very rough 
imperfect character, and we require more exact and 
complete records before we can determine the exact 
heights of the streaks and the motions of the outer 
atmosphere. However, the discussion so far as it 
has gone proves that the streaks are usually from 
fifty to sixty miles high, and that their motion is 
often more than one hundred miles an hour. A very 
destructive hurricane on the earth’s surface would 
about equal this, so that it is certain that the upper 
tenuous air is influenced by currents of far swifter 
character than the atmosphere immediately overlying 
the earth. 
If observers of meteors will only carefully record 
meteoric streaks and trains whenever they are seen we 
shall soon be in a position to ascertain more trust- 
worthily and definitely the behaviour of these curious 
afterglows. From balloon ascents it has been con- 
cluded that the general drift of the air in the region 
of ten or fifteen miles altitude is to E. and S.E., and 
this precisely accords with the direction of the majority 
of meteoric trains between about fifty and sixty miles 
high. W. F. DENNING. 
Bristol, July 13. 
Glimatic Change. 
I HAVE just seen the translation of Prof. Albrecht 
Penck’s lecture on ‘‘ The Shifting of the Climatic Belts,” 
printed in the Scottish Geographical Magazine for 
June, 1914. The main line of the author’s argument 
is that certain lakes—e.g, Lake Chad in the Sahara, 
the lakes of Mexico City, and of the Titicaca basin, 
being very slightly salt, indicate an increasing pre- 
cipitation, and during the so-called ‘ pluvial period” 
were drier than at present, owing to a shifting of the 
arid belt equatorwards. 
Surely it is more reasonable to attribute the com- 
paratively slight salt content to the fact that the 
basins have only recently ceased to have an outlet, 
owing to a decrease in the precipitation. A slow 
fluctuating decrease in the rainfall of Mexico has been 
practically proved by Prof. Ellsworth Huntington 
(e.g. ‘The shifting of climatic zones as illustrated in 
Mexico,” Bull. Amer. Geogr. Soc., vol. xlv., LOM 
Jan._Feb., and also his recent memoir on _ the 
“Climatic Factor ’’). In the case of Lake Chad, 
K. v. Zittel, an accomplished observer, describes 
evidence of a former greater extent (Palaconto- 
graphica, vol. xxx., 1883, p. 39). Information as to 
whether the lake has an old outflow channel would be 
valuable. 
So long ago as 1876 A. Agassiz, in his ‘‘ Hydro- 
graphic Sketch of Lake Titicaca’’ (Proc. Am. Acad., 
vol. xi., 1876, p. 268), wrote: ‘‘The whole of this 
district is receiving a much smaller waterfall than in 
former times.” 
Prof. Penck is unfortunate in his examples; the 
weight of evidence against him, pointing to a former 
moister period on the equator side of the arid belts, 
is too great to be ignored. And as he admits desic- 
cation on the poleward sides of these belts, the facts 
suggest that the dry area may vary in breadth as 
well as in position, and that the “ pluvial period’’ had 
a real existence—outside the glaciated regions, 
Cuas. E. P. Brooks. 
Roseleigh Avenue, Highbury, N. 
July 17. i 
NO. 2334, VOL. 93]| 
ae 7 ” 
Homeleigh,”’ 3 
NATURE 
[Jury 23, 1914 
THE PLUMAGE PROGIBITION BILL. 
poe” these lines are published the fate 
of the Plumage Prohibition Bill may have 
been decided. It seems little to our credit that 
London should be the chief market for the nefari- 
ous traffic which this Bill was framed to abolish; 
and this view was surely endorsed by the House 
when, on the second reading, the Bill was passed 
by a majority of nearly three hundred. Neverthe- 
less, during the committee stage the Bill was 
virulently opposed by a_ small, well-organised 
minority, including some actually engaged in the 
sale of plumage for millinery purposes. 
Unfortunately, the hands of the opposition hav 
been strengthened by the action of “The Commit- 
tee for the Economic Preservation of Birds ””—a 
committee which, strangely enough, does not con- 
tain the name of a single ornithologist of repute. 
So completely have these opposing forces con- 
trived to play into one another’s hands that it is 
probable that, to save the Bill, it will have to be 
modified. For total prohibition a schedule will 
have to be substituted, which must be so framed 
as to secure the safety of such species as are at 
present in actual danger of extermination. 
It would be useless to urge the need of preserv- 
ing these threatened species because of their im- 
mense value as living witnesses of the evolution 
theory; for science, and scientific problems, have 
little weight in this country. But, if for no other 
reason than that of its inhumanity, this ghastly 
traffic should be ended. 
The contention that if this Bill passes a large 
number of workpeople will be thrown out of em- 
ployment has been shown, on figures furnished 
by the trade itself, to be without justification. 
Equally groundless is the assertion that the plac- 
ing of the Bill on the Statute Book will simply 
divert the trade to Paris without saving the life of 
a single bird. If there were any sort of founda- 
tion for this, the French Chamber of Commerce 
would not have implored the British Government 
to throw out this Bill. Furthermore, we are 
assured that if this Bill passes, Germany will 
follow our lead. This done, the plume-trade in 
Europe is dead. 
If only an emasculated Bill succeeds in running: 
the gauntlet of trade interests a step in the right 
direction will have been achieved. If, on the 
other hand, the present Bill is defeated, then it 
is fervently to be hoped that a new Bill will be 
introduced at the earliest possible moment; and 
having regard to the voting on the second reading 
of the present Bill, there is every reason to regard 
its success as assured. 
SPACE AND TIME.} 
iE ROM this time forth space and time apart 
from each other are become mere shadows, 
and only a kind of compound of the two can have 
any reality.” So spoke Herrmann Minkowski in 
1908. But his statement has not yet been realised. 
1H. A. Lorentz, A. Einstein, H. Minkowski: Das Relativitatsprinzip. 
A Collection of the Classical Papers in the Deve'opment of the Theory of 
Relativity, from 1895 to 1910. Pp. 89, with portrait of Minkowski. 
(Leipzig : B. G. Teubner, 1913.) Price 3 marks. 
