682 
Mr. Louis StroMEYER, of Kolar Gold Field, Mysore 
State, South India, whose book “ The Constitution of 
the Universe ’’ was noticed in our issue of March 10, 
p. 319, has sent us a courteous protest against the 
review, particularly on the ground that it contained 
no direct detailed criticism of his theory. He con- 
tends that the review ‘‘ would have been more to the 
point had it averred that the theory was incompre- 
hensible and thus could not be criticised at all.”’ This 
was substantially our view, with the addition that 
such parts as could be understood were so frequently 
wrong as to exclude the author from any right to 
serious and lengthy attention in our columns. 
WE have received a letter from Mr. Leonard Hawkes 
with reference to Dr. Jeffreys’ conclusion (noticed in 
Nature of April 28, p. 585) that the Pamir earth- 
quake of February 18, 1911, was the result of a great 
landslip. Mr. Hawkes directs attention to the view 
that the earthquake originated at a considerable 
depth below the surface and was itself the cause of 
the landslip. The point is dealt with by Dr. Jeffreys, 
who considers that the energy in the seismic wave was 
approximately equal to that which would be developed 
by the impact of the falling mass on the ground, and 
not greatly in excess, as it would have been if the 
rock-mass were loosened by a deeply-seated earth- 
quake. 
Owi1nc to the proportions to which it has grown, 
the book department of Benn Brothers, Ltd., has 
been formed into a separate branch of the business, 
to be known as Ernest Benn, Ltd. Sir Ernest Benn, 
chairman of Benn Brothers, Ltd., will be chairman 
also of the new company, and the managing director 
NATURE 
[May 19, 1923 

will be Mr. Victor Gollancz, who for the past two 
years has been manager of the book department of 
Benn Brothers, out of which the new business has 
developed. This development will involve no change 
in general direction or financial control, and the 
address is the same as that of tHe parent company, 
namely, 8 Bouverie Street, London, E.C.4. 
A SPECIMEN of a new fountain pen, called the 
“Research Fountain Pen,’’ has been submitted to 
us by the manufacturer, Mr. A. Munro, 65 Preston 
Road, Winson Green, Birmingham, and we have used 
it with muchsatisfaction. The pen has two reservoirs, 
one of which is first filled with ink in the usual way, 
and the ink is afterwards transferred as required to 
a reservoir at the nib end by pulling out a knob and 
pushing it in again. The walls of the reservoirs are 
made of celluloid, so that the amount of ink in either 
of these can be clearly seen. It is claimed that the 
pen will not blot or leak, and that when it contains 
ink it will always write without being shaken. The 
pen certainly has some decided advantages, and so 
far as we have tested it the claims made are fully 
justified. ' 
Messrs. W. HEFFER AND Sons, Ltp., Cambridge, 
have in the press ‘‘ The Expert Witness,” by C. 
Ainsworth Mitchell, which will deal with, among 
other things, methods of identification by means of 
patterns on the feet; by the pores of the skin; by 
the detection of latent prints on paper, etc. ; methods 
of estimating the age of ink in writing, and the 
application of X-rays to the identification of old 
masters. j 

Our Astronomical Column. 
May Meteors.—Meteoric phenomena are usually 
somewhat scarce in May, but fireballs are often more 
abundant than in other months. The chief display 
of shooting stars, next perhaps in importance to the 
Aquarids of Halley’s Comet, is a shower radiating 
from a position eastwards of Corona/and near ¢ 
Herculis at about 247°+29°. They are swift white 
meteors of average magnitude and moderately short 
paths, and have been most plentifully observed on 
about May 18 and 24, but further observations are 
required to determine the epoch of maximum.  Fire- 
balls are occasionally recorded from Scorpio and from 
the western region of Aquila in May, and a few very 
slow-moving meteors are seen in some years from 
near Capella. Although the meteors visible at this 
time of the year are not equal in number to those 
appearing on autumn nights, they are of considerable 
interest, and have never been sufficiently observed. 
The bulk of the observations in this department of 
astronomy has been accumulated in the last half 
of the year, and it follows that many of the meteoric 
systems visible in the spring season have been 
comparatively neglected. 
IRREGULARITIES IN THE Moon’s Mortion.—Prof. 
Newcomb regarded the irregularity in this motion, 
the period of which is about 2} centuries, as the 
most perplexing enigma in astronomy. Mr. Walter 
Child, of Ashford, Middlesex, has made a suggestion 
NO. 2794, VOL. 111] 

which, although of no practical value, is worth men- 
tioning, as it recalls one of the exact solutions of the 
3-body problem. He points out that there is a 
conical space behind the moon, 83,000 miles long, 
which is perpetually invisible to us. In this space 
he locates a moonlet, which he supposes to influence 
the moon’s motion. It is true that there is an exact 
solution of the 3-body problem with the bodies in a 
straight line. The distance behind the moon comes 
out almost 40,000 miles for a particle of small mass ; 
it would be greater if the mass were comparable with 
that of the moon (Mr. Child’s diagram places it much 
too near the moon). It is also true that the larger 
solar perturbations on the particle would be the same 
as those on the moon, since they depend only on the 
ratio of mean motions. But in view of the fact that 
the configuration would involve an incredibly exact 
adjustment, and is unstable, it is undeserving of 
serious consideration. Moreover, Mr. Child does not 
explain how the arrangement could give rise to 
perturbations of long period without causing any 
short-period ones. Strangely, he seems to imagine 
that the moon’s librations stand in need of explana- 
tion; the extraordinary thing would be if they failed 
to exhibit themselves. They are the natural con- 
sequence of an appreciably uniform rotation combined 
with an orbital motion that is far from uniform ; also 
of the inclination of the moon’s equator to the orbit- 
plane. 
