AvuGuUST 15, 1912] 
NATURE 
617 
perihelion was also shown, the actual diameters on 
September 18 and October 28 respectively being 
1,200,000 kms. and 510,000 kms. A similar increase 
in the breadth of the ‘neck’? between the head and 
the tail was also conspicuous. On the former date 
the head was 54’ in diameter, while the neck was only 
6’, but as the comet approached the sun this disparity | 
disappeared, the increased rush of matter from the 
head, consequent upon the greatly increased light- 
pressure, probably accounting for the phenomenon. 
OBSERVATIONS OF JupIrER.—The observations of 
Jupiter made, during the present opposition, at the 
Juvisy Observatory are described and illustrated by 
M. Quénisset in the August number of L’Astronomie. 
Among other remarkable changes taken place since 
last year, it is noted that the great northern equatorial 
band is much feebler, more irregular, and less definite 
than in 1910 and 1911, while the north temperate band 
is, at present, much darker and broader than before ; 
it also appears to be nearer the North Pole. The 
acceleration of the Great Red Spot has been so marked 
that in the middle of July it passed the central meri- 
dian th. 4om. before the zero meridian of system ii. 
The observations indicate a displacement of 22° per 
annum, equivalent to 25,500 kms. on the planet’s 
surface, or about twice the earth’s diameter. Another 
important feature, the south tropical spot, is darker 
and more defined than last year, but is not so ex- 
tended. As it passes the central meridian an hour 
after the zero meridian of system ii., it is unlikely that 
the interesting conjunction of these two great spots 
will be observable during the present opposition. 
Observations made during June at the French 
Astronomical Society’s observatory show that the 
southern disturbance has, since June, 1911, preserved 
its speed of 7° per month, but later observations indi- 
cate an acceleration which will make the new speed 
15° per month. 
A New SvupPLEMENT TO THE ASTRONOMISCHE NACH- 
RICHTEN.—A supplement, No. 1 of the Literarisches 
Beiblatt su den Astronomischen Nachrichten, July, 
1912, Band 192, appears with No. 4593 of the journal. 
Its object is to notice briefly numerous papers appear- 
ing in other current astronomical journals, to publish. 
short notices of new astronomical books, and, in 
general, to keep its readers aw courant with what is 
taking place in astronomical science. . The output of 
new knowledge in astronomy is now so enormous that 
it has been found impossible to deal with these refer- 
ences and notices in the parent journal. 
Tue VariaTION oF LatirupE.—In the latitude varia- 
tion carefully observed at the International Latitude 
stations during the past twelve years, there is a term, 
the Kimura term, as yet unexplained. This is dis- 
cussed by Dr. F. E. Ross in No. 4593 of the Astro- 
nomische Nachrichten, and it is suggested that the 
effect represented by the term is a physical one caused 
by a progressive change of the zenith point through- 
out the night at a rate varying with the season. The 
matter is undoubtedly a very complicated one, in 
which a secular refraction starting at sundown and 
depending upon the progressive approach of the mean 
equivalent isobaric surfaces to the ground is concerned. 
Dr. Ross suggests the installation of two special lati- 
tude stations on the equator, 180° apart and at high 
altitudes (e.g., Quito and near the west coast of 
Sumatra) for the further elucidation of the matter. 
Tue Orsits or Comets.—Commenting on a sugges- 
tion made by Prof. Kobold that the orbits of all the 
hyperbolic comets, if properly corrected for the per- 
turbations of the known planets, would be found to 
be parabolic, Prof. W. Pickering points out that the 
hyperbolic orbits appear to be fairly sharply differen- 
NO. 2233, VOL. 89] 
tiated from the parabolic by the fact that their aphelia 
tend to collect near one great circle of the sphere, 
while those of the parabolic collect near another great 
circle, which intersects the first at an angle of 74°. 
Thus 73 per cent. of the hyperbolic orbits lie within 
a zone comprising only 34 per cent. of the total area 
of the sphere, while 68 per cent. of the well-deter- 
mined parabolic orbits, 31 in all, lie within the other 
of the two zones. The inclination of the ‘ hyper- 
bolic’? zone to the ecliptic is 860°, and the longitude 
of its node is 934° (Astronomische Nachrichten, No. 
4593): 
THE MINERAL RESOURCES AND 
DEVELOPMENTS IN THE UNITED STATES.} 
Pee mineral industry of the United States reached 
its greatest prosperity in the year 1907. In the 
following year it shared the depression which affected 
American trade; but in 1909 there was a rapid recovery, 
and the statistics of the mineral production give im- 
pressive testimony to American wealth and resources. 
The output of coal was 460,000,000 short tons, which 
is 37°53 per cent. of the total for the world; the 
British output is second in size, and is a quarter of 
the total. The supremacy of the United States in 
copper production is still more marked, its yield being 
more than 58 per cent. of the total, and in spite of the 
commercial panic the output for 1g08 and 1909 showed 
a steady increase above that of 1907. In spite of the 
low price ot copper, a still larger yield is expected 
for 1911, when some large low-grade mines in Arizona 
began their contributions to the supply. 
The two volumes on the mineral resources are 
crowded with figures which indicate that the reserves 
of the essential minerals are increasing even more 
than the demands upon them, as lower grade materials 
can be used and fresh stores are discovered. Thus 
the yield from the alluvial gold deposits of California 
is increasing, owing to the use of dredges, which 
recovered gold worth 7,382,950 dollars in 1909, in com- 
parison with values of 5,065,437 dollars and 6,536,189 
dollars in 1907 and 1908 respectively. The deep gold 
mines of California also increased their output, and 
Nevada has raised its gold yield by 60 per cent. Even 
in regard to the two minerals which are probably the 
most readily exhausted, natural gas and oil, the yields 
show continued increase. The annual value of the 
natural gas produced in the United States rose from 
215,000 dollars in 1882 to more than twenty-two 
million dollars in 1888; it then fell year by year to 
thirteen millions in 1896; but ever since it has shown 
a steady rise to its record of 63,206,941 dollars in 1909. 
Pennsylvania, with 9,313 wells, is still the State pro- 
ducing the largest quantity of natural gas; the 
greatest increase in 1909 was in Ohio; only a few 
States with small or insignificant outputs, such .as 
Missouri and Colorado, have been less productive. 
The statistics of oil production show that California 
is now the most prolific oil State, and has a yield 
nearly twice as great as the maximum of Penn- 
sylvania. 
The most important of the American metallic ores 
1 “Mineral Resources of the United States. Calendar Year 1909.” Parti., 
“Metals.” Pp. 617+1 plate. Part ii., ‘‘ Non-metals.” Pp. o42. (Wash- 
ington, Department of the Interior, U S. Geological Survey, r9rr.) 
Bulletin No. 451, ‘‘ Reconnaissance of the Ore Deposits in Northern 
Yuma County, Arizona.” ‘By Howland Bancroft. Pp. 130+8 plates. 
Bulletin No. 454, ‘‘ Coal Oil and Gas of the Foxturg Quadrangle; Penn- 
Seu By Eugene Wesley Shaw and Malcolm J. Munn, | Pp. 85+-10 
plates. 
Bulletin No. 455, “ Copper Deposits of the Appalachian States.” By 
Walter Harvey Weed. Pp. 166+5 plates. 
Bulletin No. 456, “Oil and Gas Fields of the Carnegie Quadrangle, 
Pennsylvania.” By Malcolm J..Munn. Pp. g2+5 plates. 
Bulletin No. 480, ‘‘ Mineral Resources of Alaska. Report on Progress 
of Investigations in r910."’ By Alfred H. Brooks and others. Pp. 333+ 
13 plates. (Washington, rorr.) 5 
