ey 
906 
including mainly meteorological, seismological, geo- 
logical, botanical, and zoological maps. A reference- 
list to persons, expeditions, and surveys, is also ap- 
pended. 
— The third series of charts published by the signal- 
service, to illustrate the studies of tornadoes under- 
taken this year, represents the storms of March 25, 
Twenty tornado-tracks are mapped, scattered over the 
states south and east of Indiana. Their times are all 
in the afternoon or evening, and their courses, as 
usual, bear about east-north-east. The results of 
these disasters are at present counted thus: number 
of persons killed, 77; wounded, 298; valuation of 
property destroyed, $950,000. ‘The contrast of the 
small, local tornado-whirls and the great sweep of 
the cyclonic circulation is clearly marked; and the at- 
titude of the tornadoes, relative to the cyclone centre 
600 MILES 
and the warm and cold winds, is seen to be about the 
same as was shown on the earlier charts for Feb. 19 
and March 11. The accompanying diagram is de- 
signed to show this relation in a general way, being 
based on an average of the three sets of charts. The 
nearly north-and-south elongation of the barometric 
depression is a departure from the more easterly trend 
of the major axis of the isobaric curves given in 
Loomis’s averages; and this peculiar form is doubt- 
less to be held in chief part accountable for the sig- 
nificantly abrupt change from the cold north-westerly 
winds of the western half of the cyclonic area to the 
warm southerly winds of the eastern half. The con- 
trast of temperature thus produced is exhibited in the 
oblique trend and close approach of the isothermal 
lines, which are drawn for ten-degree differences. 
SCIENCE. 
< ' y 
[Vor. IIL, No. 65 
But most striking is the limitation of the tornadoes 
to that part of the warm southerly winds which is 
immediately overflowed by the cold winds, and the 
advance of the tornadoes, not with the surface-cur- 
rents, but parallel to the spiral course of the cold 
blast overhead, through which the warm lower air 
ascends. ‘The limitation of tornadoes to certain parts 
of cyclones, as thus shown, is a most hopeful sign, 
that, with longer and more detailed study, the smaller 
storms may, a few years hence, be predicted with as 
much accuracy as the larger ones are now. | 
— Prof. George F. Wright has contributed a good 
article on ‘the Niagara gorge as a chronometer’ to 
the April number of the Bibliotheca sacra. 'Thecon- 
clusion is reached that the entire gorge from Queens- 
town to the Falls is the result of post-glacial cutting, 
and that the most probable rate of recession of the 
falls is about three feet a year; thus placing the end 
of the glacial period here about twelve thousand years 
ago. ‘This agrees very well with the date determined 
by Prof. N. H. Winchell from the Falls of St. 
Anthony. ‘The inconvenience to naturalists of hay- 
ing such an article as this stowed away in a theological 
magazine may be counterbalanced by the satisfaction 
they should feel on learning that it could be accepted 
there at all. 
— Arrangements have been completed for holding 
at the university library, Berkeley, Cal., during the 
last week of May, a loan exhibition of books illustra- 
tive of the history and progress of printing. 
— The government of Newfoundland has voted to 
establish a geological museum at St. Johns. Mr. 
James P. Howley, the geological surveyor, is now 
giving his whole time to it, and, before the year is 
over, the museum will be open to the public and to 
students. The collections made by Alexander 
Murray and James P. Howley are especially rich in 
orthoceratites, trilobites, and fossils of the primordial 
fauna. me? 
—A cable message received at Harvard college 
observatory announces the discovery of an asteroid 
(No. 236) by Palisa, at Vienna. Its position was, 
April 26, 40.42 Greenwich mean time ; right ascen- 
sion, 13h., Om., 43.5s.; declination south, 3° 21/ 41”; 
daily motion in right ascension, 44s.; in denomina- 
tion, N. 6°. Itis of the twelfth magnitude. 
— The Engineer of March 29 gives a new method 
of preparing wood-blocks for paving, practised by Mr. 
Mallet of Moissac. He boils them in a solution of 
sulphate of copper, sulphate of zinc, and chloride of — 
sodium, mixed with heavy mineral oil, linseed-oil, 
and tallow, and afterwards compresses them to about 
one-tenth of their original volume, 
—In our last number, p. 5038, Dr. Sturtevant’s 
quotation from the American journal of science, — 
which he attributes to Professor Asa Gray, is from a 
reprint of a portion of Dr. Carpenter’s article in the © 
Philosophical transactions. As Professor Gray’s 
name does not appear in any connection, even in j 
the introduction, and as the whole extract from Dr. — 
mistake | 
Carpenter is within quotation-marks, the 
seems unaccountable. - 
a 
- 
