588 
animals from a selected area may produce valuable 
results, both as regards knowledge of the habits 
of the fly, and as to the extent to which the in- 
fectivity of the fly and subsequently the infection 
of man or stock is derived from wild animals. The 
result of this experiment cannot be confidently 
anticipated, but, nevertheless, the committee think 
there is sufficient to justify an expectation of useful 
results and recommend that if a suitable locality 
can be found where an experiment can be carried 
out at a reasonable cost, it should be undertaken. 
RECENT STUDIES OF THE ATMOSPHERE:! 
tee German Meteorological Society offered a 
prize for the best essay on the results of the 
International Kite and Balloon ascents, and the 
prize was won by Mr. Gold in 1912 by the memoir 
which is now published by the Meteorological 
Otfice. The results mostly refer to ascents which 
took place prior to December, 1909, but in the 
case of some stations observations are included 
up to November, 1911. From an exhaustive con- 
sideration of the temperature in the free air and 
its relation to pressure at sea-level, geographical 
position, and season, it appears that in Europe 
August is, in general, the warmest month in the 
troposphere, and March the coldest, except close 
to the surface; thus, the temperature lag is 
greater for the minimum than for the maximum, 
which, as is pointed out in the memoir, is to be 
expected, for convection can carry warmth up- 
wards, but not cold. 
from the study of the upper air that a cyclone is 
colder than an anticyclone, and this is borne out 
by Mr. Gold’s figures; he finds that a cyclone is 
colder than an anticyclone up to ten kilometres, 
that is, up to the,level of the stratosphere. 
The height at which the stratosphere is found, 
and its temperature, are known to vary with the 
surface pressure; the higher the pressure the 
higher is the lower limit of the stratosphere and 
the lower the temperature of the layer. Mr. Gold 
has investigated this point in detail and gives 
diagrams showing the changes in the stratosphere 
in height and in temperature through areas of 
high and low pressure, both in winter and summer. 
The places where sounding balloons fall show that 
the general drift of the wind over Europe is from 
the north-west in the upper air. Balloons sent 
up in easterly winds usually fall to the east of 
the starting place in winter, showing that at this 
season an easterly current is shallow, the pressure 
gradient above being reversed by the gradient of 
temperature from south to north. Mr. Gold dis- 
cusses many questions of the winds and the 
dynamics of the atmosphere, but it is impossible 
1 Geophysical Memoirs (Meteorological Office) :— 
No. 5. The International Kite and Balloon Ascents, By Ernest Gold. 
(1913.) Price 1s. 6d. 
No. 6. The Free Atmosphere in the Region of the British Isles (Third 
Report). ‘The Calibration of the Balloon Instruments and the Reading of 
the Traces. By W. H. Dines, F.R.S. (1914.) Price 3a. 
_No. 7. A Comparison of the Electrical Conditions of the Atmosphere at 
Kew and Eskdalemuir, By Gordon Dobson. (1914) Price &d. 
No. 8. Lag in Marine Barometers on Land and Sea. By Dr. Charles 
Chree, F.R.S. (ror4.) Price 4d. 
NO. 2336, VOL. 93] 
It has become apparent: 
NATURE 
[AucusT 6, 1914 
in a short notice even to indicate every point in 
the work; it should be read by all interested in 
dynamical meteorology. 
Almost all the observations in the upper air in 
this country are made with Mr. W. H. Dines’s 
light meteorograph. In Geophysical Memoir, 
No. 6, Mr. Dines describes very fully the method 
of calibrating, preparing the instrument for the 
ascent, and working up the trace. With these 
instructions and those given in a former publica- 
tion of the Meteorological Office (M. O. 202) an 
observer should be able to use the instrument to 
full advantage 
Electrical observations of the atmosphere at 
the new observatory at Eskdalemuir are discussed 
by Mr. Dobson in the Geophysical Memoirs, and 
compared with those at Kew. Conditions differ 
in several respects, being far more disturbed at 
the northern station. The diurnal curves of the 
potential gradient for the two stations are similar 
during the winter, but differ markedly in the 
summer; at this season the potential at Eskdale- 
muir is high at night and begins to fall in the 
early morning when it is rising to a maximum at 
Kew. The mean absolute value of the potential 
gradient.is always higher at Kew than at Eskdale- 
muir, which Mr. Dobson attributes chiefly to the 
abnorm«zlly low conductivity of the air at Kew. 
The small and uncertain difference in the number 
of ions between summer and winter at Eskdale- 
muir is remarkable. The station has not been 
long established, and the account given in this 
memoir will, no doubt, be amplified when a 
longer series of observations from Eskdalemuir is 
available. 
The constriction in the tube of the marine baro- 
meter, made to avoid oscillations of the mercury, 
causes a lag which is discussed by Dr. Chree in 
No. 8 of the Geophysical Memoirs. The theory 
was considered by Stokes, who found that the 
marine barometer had a certain “lagging time.” 
If the sluggishness were due to the constriction 
alone the lag should be too small to affect read- 
ings in practice. But Dr. Chree has investigated 
the problem by the consideration of the readings 
of a number of barometers tested at Kew, and 
finds the lag to be considerably greater than 
according to Stokes’s formula. Further obser- 
vations with the same result were made with two 
barometers which were subsequently put on board 
ship, and read every four hours by the ship’s 
officers during a number of voyages across the 
Atlantic; the lag at sea was found to be much 
less than on land, and was almost entirely con- 
fined to cases where the barometer was “ pump- 
ing.” No explanation is put forward to account 
for “the extraordinary difference between land 
and sea results.” Dr. Chree is not of opinion 
that it can be explained by uncertainties of read- 
ing at sea. Further observations are hinted at, 
and it is certainly desirable to find out why on 
land the lag should be ‘enormously greater ” 
than given by Stokes’s formula, while at sea it is 
“exceedingly small.” 
