PS ot 
Aprit 18, 1912] 
NATURE 
7s 
connection between the advance of a barometric de- 
pression and the sea-seiches observed at eight ports 
in Japanese waters. 
THE new catalogue of physical apparatus issued by 
Messrs Baird and Tatlock (London), Ltd., is a quarto | 
volume of 650 pages, and is well illustrated. It con- 
tains descriptions of several new pieces of apparatus, 
as, for example, the induction solenoids on p. 536, 
and Milner’s automatic mercury pump. It would be 
an advantage if British instrument makers would in 
their new catalogues cease to figure and describe 
apparatus hopelessly out of date, like Lavoisier and 
Laplace’s ice calorimeter. 
Tue theory of the universe which was propounded 
eight years ago by the late Prof. Osborne Reynolds in 
his “‘Sub-mechanics of the Universe’’ has found a 
popular exponent in the person of Mr. J. Maclxenzie, 
a copy of whose lecture on the subject, delivered 
before the Minnesota Academy of Sciences and the 
American Association for the Advancement of Science 
at Minneapolis, has just reached us. It contains a 
clear account of a theory which is not by any means 
easy to follow in the original, and is illustrated by 
several figures of Prof. Reynolds’s experiments, 
including that of the thin indiarubber bag partly filled 
with sand which supports 200 Ib. on its edge. <A 
good portrait of the late professor serves as a frontis- 
piece. 
SpeciaL PusticaTion No. g, 1911, of the U.S. Coast 
and Geodetic Survey contains a magnetic declination 
chart for the United States for the epoch January 1, 
1910. It also gives secular change data—in continua- 
tion of similar data in earlier publications—for a 
number of selected stations. In the east, westerly 
declination is increasing more rapidly than in 1905. 
In the North Atlantic States, where the change is 
most rapid, it is now about 6! a year. 
territories easterly declination is increasing, also more 
rapidly than in 1905. The rise is now as much as 5/ 
a year in some places a little inland from the Pacific 
coast. The changes in progress at present throughout 
the United States are so complicated that it is impos- 
sible to predict their course even a few years ahead. 
Ir has long been known that traces of hydrogen 
peroxide are found in rain water and in snow, and 
that during the day the proportion is greater than 
at night. In 1909 it was shown by Miroslaw Kern- 
baum that the ultra-violet rays from a quartz mercury- 
vapour lamp decompose water according to the equa- 
tion 2H.O=H.O.+H., a fact which suggests that 
the hydrogen peroxide in rain water owes its forma- 
tion to the action of solar ultra-violet rays on water 
vapour in the upper region of the air. The correct- 
ness of this hypothesis has been since verified by M. 
Kernbaum (Bull. International Acad. Sci. Cracovie, 
191i, p. 583), who finds that ordinary sunlight even 
at the earth’s surface is capable of demonstrably pro- 
ducing the same result in water enclosed in a quartz 
flask, both hydrogen and hydrogen peroxide being 
formed in minute quantities after a few days’ expo- 
sure to the rays of the sun in July. In such a case 
the action of the ultra-violet rays is necessarily less 
NO. 2216, voi. 39] 
In the western | 
| 
| faded away almost directly. 
| interest at the present juncture, 
than in the upper atmosphere, owing to their absorp- 
tion in passing through the air. 
An illustrated description of the Ljungstrém steam 
turbine appears in Engineering for April 12. This 
machine is of the reaction type, and has been designed 
by its inventor—a Swedish engineer—so as to avoid 
some of the defects which are inherent to this kind 
of turbine. The flow is radial, the steam being 
admitted between two discs, and in its passage from 
their centre to their circumference, passing between 
concentric blading rings carried alternately by the two 
discs. In the usual design, both the discs revolve, 
driving their shafts at equal speeds, but in opposite 
directions, and to each shaft is coupled an electric 
generator. The relative speed of each set of blades 
is thus twice as great as in a standard reaction tur- 
bine of equal revolutions and diameter, hence for 
equal efficiency the total number of blade rows is only 
one-quarter as great. By the disc arrangement dis- 
tortion troubles are avoided, hence the machine lends 
itself to the use of steam superheated to the highest 
degree. The general design makes an astonishingly 
small turbine for the power developed. Experiments 
have been made with a 500-kw. machine, and one of 
1ooo-kw. capacity has just been finished and 
thoroughly tested. 
OUR ASTRONOMICAL COLUMN. 
THE SOLAR EcLipsE OF APRIL 17.—At the moment of 
going to press, the following telegram has reached us 
from Dr. Lockyer and Mr. F. Maclean, vid Paris :— 
*Camp American line on road three-quarters mile 
north-east Chavenay practically central Bailey’s 
Beads no corona prominences eight and two o’clock 
duration about two seconds. Weather perfect.— 
Lockyer, Mactean.”’ 
A DayiicHt Mereor.—Mr. Hugh Ramage, 
organiser of higher education, Norwich, sends us 
some extracts from The Eastern Daily Press of April 
3, 4, 6, and 8, containing observations of the daylight 
meteor of March 28, referred to last week (p. 147). 
Mr. W. F. Bushell, Gresham’s School, Holt, states 
that the meteor was observed at about 2.45 p.m. ‘t 
was seen by several observers, who agree in stating 
that “it left behind a yellowish-green track, which 
The meteor appeared in 
the northern part of the sky, and seemed to be travel- 
ling in an easterly direction. The sun was shining 
at the time.” 
Tue Nova, OR VARIABLE, IN PERSEUS, 87°1911.—The 
supposed nova discovered by Mr. D’Esterre is the 
subject of some further notes in No. 4564 of the 
Astronomische Nachrichten. This object is of especial 
when so many 
attempts are being made to explain the appearance 
of nove, for it appears to consist of several condensa- 
| tions, of changing aspects, surrounded by nebulosi- 
ties, or themselves nebulous. Whatever the object 
itself may be, it is evident that the region is one of 
considerable interest, which should be carefully 
examined with more powerful instruments. 
A New Star CataLocue.—Astronomers are indebted 
to Mr. Backhouse for a valuable new star catalogue 
of 9842 stars, containing all stars very conspicuous 
to the naked: eye. The catalogue is intended as a 
complement to a set of maps designed especially for 
the use of meteor observers, but should be found very 
useful by all astronomers. In addition to the various 
