710 
purpose. A very large part of the meteorological 
vocabulary is unfamiliar to meteorologists. This 
is illustrated by the case of the ‘‘isograms.’’ 
Upwards of eighty of these lines have been given 
appropriate names; but not a score of these names 
are in current use. 
In no branch of science is the vocabulary more 
confused than in atmospheric optics; especially in 
English. One can hardly write of any but the 
commonest photometers without defining almost 
every term one uses. Thus the words ‘‘glory,’’ 
‘“eorona,’’ ‘‘aureole’’ and ‘‘anthelion’’ are vari- 
ously applied and interchanged; the Brocken 
specter is confused with the Brocken bow; etc. 
Among meteorological neologisms the term 
‘Caerology,’’ meaning the branch of science con- 
cerned with free-air investigations, deserves a 
wider use; ‘‘stratosphere’’ is the best name for 
the region of the atmosphere now more generally 
called the ‘‘isothermal layer’’; Arctowski’s terms 
‘‘pleion’’ and ‘‘antipleion’’ are useful additions 
to the vocabulary; Dr. H. R. Mill’s discrimination 
of ‘‘mean,’’ ‘‘average’’ and ‘‘general’’ will ob- 
viate the confusion that heretofore reigned in the 
use of these words; the application now given in 
Great Britain to the terms ‘‘rime’’ and ‘‘glazed 
frost’’ is commended to general attention; L. Bes- 
son’s name ‘‘nephometer’’ seems appropriate for 
an instrument used to measure the amount of 
cloudiness; the derivatives of the new German 
names for the snow-gauge (‘‘chionometer,’’ 
‘¢nivometer’’) are likely to come into general 
use (%. €., we shall use ‘‘nivometric,’’ ete., though 
we may not adopt the noun); Odenbach’s ‘‘cer- 
aunograph’’ is a good international name for 
the thunderstorm-recorder; the American name 
‘¢kiosk’’ gives us a tolerable English equivalent 
for ‘‘ Wettersaiile.’’ 
An international commission on meteorological 
terminology is an urgent desideratum. 
Can Astronomy Deriwe Benefit from the Dissem- 
ination of Esperanto? F. H. Loup. 
The paper first pointed out some of the easily 
verifiable indications of the entrance of Esperanto 
upon the stage of practical utility in the ordinary 
relationships of life, and proofs of the increasing 
popular acquaintance with it, especially in Europe; 
and then, passing to the consideration of its pos- 
sible utilization in the service of astronomy, sug- 
gested its employment (1) in the oral discussions 
and the reports of international conventions, (2) 
in astronomical treatises, where, in the field of 
pure mathematics, for instance, such an example 
SCIENCE 
[N. S. Vou. XXXV. No. 905 
has already been set as the work of Dr. Cyril 
Vorods, of Budapest, on ‘‘Absolute Geometry’’— 
a book (including its three sections) of 439 
pages, and of high scientific value, and (3) in the 
dissemination of astronomical news, through the 
Internacia Science Asocio and other channels, 
where, though the direct service were rather to 
the general public than to professional astron- 
omers, yet the science would ultimately receive 
benefit. 
On the Flexure of a Meridian Circle: W. S. 
EICHELBERGER and H. R. MorGan. 
From 1903 to 1911 the flexure of the 9-inch 
transit circle of the Naval Observatory was deter- 
mined from measures on collimators. The circle 
was shifted for each of the six clamp years, and 
at the end of the work, and the circle flexure dis- 
tinguished from the tube flexure. 
The table gives the division of the circle at the 
object glass end, the means of the measures on 
the collimators for each position, and the residuals 
from the solution of the fourteen equations. 
The first eight equations result from 70 sets of 
measures on the horizontal collimators, and the 
last six from 68 sets of measures on the vertical 
collimator and nadir. 
OO) WinOlaG 
Zs+ycos (A—270° 47) =—0".95 3 +0711 
r+ y cos (A — 269° 56’) =—1".14 6 —0”.08 
Zs + y cos (A — 264° 52’) =—1”.02 6 —0”.04 
Z3 + y cos (A — 259° 40’) =—0”.74 13 + 07.16 
ts + y cos (A — 256° 28’) =—0”.99 18 —0/.15 
Zt y eos (A — 261° 34’) =—0”.89 6 + 07.04 
Zs + y cos (A — 261° 16’) =—0”.85 9 + 0".07 
ts +yeos (A— 81°16’) =+ 07.35 9 0”.00 
Ge — y sin (A — 264° §2’) =+1”.08 10 + 07.12 
%e— y sin (A — 259° 40’) = + 0”.85 14 + 07.17 
%e— ysin (A — 256° 28’) =+ 17.13 12 + 07.08 
Ze—y sin (A — 261° 34’) =+ 1”.07 14 +4 07.07 
@e— ysin (A — 261° 16’) =+ 0”.93 9 + 07.07 
Ze—ysin (A— 81° 16’) =—0”.96 9 —0”.03 
The solution gave: the coefficient of the sine flex- 
ure of the tube, 7; =— 0”.289; the coefficient of 
the cosine flexure of the tube, 2,=- 07.037; 
the coefficient of the flexure of the circle, 
y==-+1”.156; the point of maximum weight of 
the circle, A =137° 55’. To test the sine law, 264 
direct and reflected star observations were taken, 
on both clamps, and both sides of the zenith. The 
solutions in the table give the error of the nadir, 
or cosine flexure; a term for bisection error, or 
other discontinuity at the zenith; and the sine 
flexure. 
