860 
class of species. Mr. Pollard briefly described 
a short collecting trip in West Virginia and 
Virginia. 
THE eleventh regular meeting was held at 
the residence of Mr. C. L. Pollard, Novem- 
ber 1, 1899. The election to active mem- 
bership of Mr. William R. Maxon, of the 
United States National Museum, was an- 
nounced. Mr. C. L. Shear spoke of his dis- 
covery of a trufile, Terfezia oligosperma, in 
Maryland, stating that this was the first record 
of its appearance in the United States. His 
remarks were illustrated by specimens and by 
microscope slides. Mr. J. N. Rose described 
the mescal industry of Mexico, exhibiting 
photographs of the mescal plant itself and of the 
mode of preparing the liquor, a sample of 
which was passed around among the members. 
Mr. L. H. Dewey gave an account of various 
weeds observed by him on a trip through the 
southern states during the past summer ; the 
most prevalent species, he considered, were the 
following: Leptilon divaricatum, Diodia teres, 
Cassia occidentalis, C. Tora, Helenium tenuifo- 
lium, Croton capitatus, and Solanum rostratwm. 
Mr. Pollard exhibited the first decade of a dis- 
tribution of North American Violaceze under- 
taken by Professor Greene and himself. Pro- 
fessor John M. Coulter, of the University of 
Chicago, who was present as a guest of the 
Club, gave a short address on the organization 
and aims of the department of botany in that 
institution. CHARLES L. POLLARD, 
Secretary. 
DISCUSSION AND CORRESPONDENCE. 
THE SCIENCE OF METEOROLOGY. 
To THE EDITOR OF SCIENCE: In reading the 
admirable address by Dr. Marcus Benjamin, in 
your JOURNAL of November 34d, it occurs to me 
that the learned Doctor is rather hard on me- 
teorology when he speaks of ‘‘ that science which 
we now dignify by the name of meteorology’’ (see 
page 628). Are we to understand that this 
science has recently been dignified by giving it 
this new baptismal name? Have we of the 
present generation devised this dignified name 
for a new branch of science? My understand- 
ing is that meteorology as a branch of philo- 
sophical study is quite as old as astronomy, if 
SCIENCE. 
[N. S. Vou. X. No. 258. 
not older, and that the name ‘meteorologia’ 
originated with that profound school of philos- 
ophy of which Plato and Socrates were the ex- 
pounders. To them, or possibly even to their 
predecessors, we owe the system of nomencla- 
ture ‘astronomia,’ ‘meteorologia,’ ‘ geometria,’ 
etc., by which they designated the various 
branches of knowledge. Doubtless, Dr. Ben- 
jamin meant to refer to ‘that science which 
Plato and Socrates dignified by the name of 
meteorology.’ The correction is worth making 
in order that your readers may not forget that 
the study of the atmosphere has from the most 
ancient times been recognized as a distinct 
branch of science. (Oh z\ 
NOTES IN PHYSICS. 
THE MAGNETIZATION OF LONG IRON BARS. 
Dr. C. G. Lams, in the Philosophical Maga- 
zine for September, gives some interesting ex- 
perimental results concerning the distribution 
of magnetic induction along a long cylindrical 
iron rod. When the rod is weakly magnetized, 
the mean positions of its poles are comparatively 
near the ends of the rod ; with stronger mag- 
netization the poles move farther from the 
ends ; and with very strong magnetization the 
poles move more and more towards the ends. 
This result, as Dr. Lamb points out, has im- 
portant bearing upon the magnetic testing of 
iron by Ewing’s method. 
THE VELOCITY OF THE CHARGED AIR 
PARTICLES NEAR A DISCHARGING 
METAL POINT. 
Proressor A. P. CHATTOCK in the Philosoph- 
ical Magazine for November, gives the results 
of avery ingenious determination of the veloc- 
ity of the charged air particles: or ions in the 
electrical discharge from a metal point. He 
finds the velocity to be 413 centimeters per 
second for positive ions, and 540 centimeters 
per second for negative ions, both for an electric 
field of 300 volts per centimeter. This result 
is in remarkable agreement with the velocities 
of the air ions which are produced by X-rays 
and by uranium radiations. Professor Chattock 
also shows that the velocity of the wind which 
blows from a discharging point is not greater 
than 2 per cent. of the velocity of the ions, and 
