Vol. XXV. No. 10.] 
POPULAE SCIENCE NEWS. 
155 
In review, the past summer is shown to have 
been cooler than usual, far more cloudy and 
rainy, with more easterly and northerly winds, 
and a higher pressure, with small, but larger 
daily movements than usual. D. VV. 
Natick, Sept. 5, 1891. 
[Specially Computed for Popular Science News.] 
ASTRONOMICAL PHENOMENA FOR 
OCTOBER, 1891. 
At the beginning of the month Mercury is a 
morning star; having passed greatest western 
elongation on September 28 it is now approaching 
the sun, but is still far enough away to be seen in 
the early morning twilight nearly above the place 
where the sun will rise. It is in rather close con- 
junction with Saturn on the morning of October 
3. At the time of nearest approach (2 A. M.) the 
latter is 12' — or a little more than one-third of the 
moon's diameter — north of the former; but this 
distance will have increased considerably when 
they rise above the horizon in the western hemis- 
phere. Mercury rapidly approaches the sun, and 
passes superior conjunction on the evening of 
October 27. Venus passed superior conjunction 
with the sun on the morning of September 18, and 
is now an evening star, but does not attain a great 
enough distance to be a very conspicuous object 
during the month. However, it may possibly be 
seen toward the end of the month low down in 
the western horizon, a little south of the place 
where the sun went down. Mars is a morning 
star, rising an hour before the sun on October 1, 
and more than two hours before on October 31. 
It passed aphelion on September 29 and conjunc- 
tion on .July 30, so that it is now drawing near 
the earth ; but the diminution of distance is not 
great, and it is not a conspicuous object. It is 
moving rapidly eastward among the stars. At 
the end of the month it is about 3° west of the 
third magnitude star Gamma Virginis, and is mov- 
ing toward it. A good idea of the apparent mo- 
tions of the planets among the stars may be ob- 
tained by watching it during the coming months, 
as it moves toward opposition next summer. 
Jupiter is the only one of the planets in really 
good position for evening observation. It is on 
the meridian at about 10 P. M. on October 1, and 
two hours earlier at the end of the month, and 
sets about five hours after meridian transit. The 
following eclipses of its satellites may be seen 
from some part of the United States, llie phe- 
nomena take place off the right-hand limb of the 
planet, as seen in an inverting telescope. D. de- 
notes disappearance; R., reappearance. Times 
are Eastern Standard. 
October 1, 8h. 8m. P. M. 
October .5, 8h. 21m. P. M. 
October 0, Ih. 2.5m. A. M. 
October 7, 7h. 53m. P. M. 
October 8, lOh. 44m. P. M. 
October 12, 9h. 11m. P. M. 
October 13, 12h. 23m. A. M. 
October 14, 9h. 49m. P. M. 
October 16, Ih. 20m. A. M. 
October 20, Ih. 13m. A. M. 
October 20, 4h. 24m. A. M. 
October 21, llh. 45m. P. M. 
October 23, 6h. 13m. P. M. 
October 29, lb. 40m. A. M. 
October 30, 8h. 9ra. P. M. 
Saturn is a morning star, rising a little more 
than an hour before the sun on October 1, and 
about three hours before on October 31. Mars 
passes it on the south, at about a degree distance, 
on October 12. The rings reappear on October 29, 
on account of the sun passing to the same side of 
their plane which the earth occupies. It is still 
II. 
R. 
III. 
R. 
I. 
R. 
I. 
R. 
ir. 
R. 
III. 
D. 
III. 
R. 
I. 
R. 
II. 
R. 
III. 
D. 
III. 
R. 
I. 
R. 
I. 
R. 
I. 
R. 
I. 
R. 
in the constellation Leo, and is 9° south'of the 
second magnitude star Beta Leonis. Uranus is in 
conjunction with the sun on October 25. Neptune 
is a morning star in the constellation Taurus, 4° 
north of the first magnitude star Aldebaran. 
The Constellations. — The positions given hold 
good for latitudes differing not many degrees 
from 40° north, and for 10 P. M. on October 1, 
9 P. M. on October 15, and 8 P. M. on October 31. 
The small constellation Lacerta is in the zenith. 
Pegasus is just below it, to the south, on both 
sides of the meridian. Aquarius is on the south 
meridian, about half-way up, and below it is Pis- 
cis Australis. Cetus is low down in the south- 
east. Pisces follows Aquarius, and is just below 
Pegasus. Andromeda is high up, a little north of 
east ; and below it are Aries, a little to the right, 
and Taurus, lower down, a little to the left. Per- 
seus is about half-way up, in the northeast, and 
Auriga is below it. Cassiopeia is coming to the 
meridian y between the zenith and the pole; and 
Ursa M.ajor is on the north horizon, with the 
pointers on the meridian below the pole. Urs.a 
Minor is mainly to the left of the pole star, and a 
little below; and Draco is to the left of Ursa 
Minor. Cygnus is to the west of the zenith. 
M. 
Lake Forest, III., Sept. 1, 1891. 
QUESTIONS AND ANSWERS. 
Letters of inquiry should enclose a two-cent 
stamp, as well as the name and address of the 
writer, which will not be published. 
Questions regarding the treatment of diseases 
cannot be answered in this column. 
W. C. C, Philadelphia. — It is stated that storage 
batteries when charged lose a large part of their 
power by leakage. What is the cause of this leak- 
age? 
Answer. — No electricity is really, "stored" in 
these batteries, and they do not difl'er in their 
mode of action from the ordinary battery, where 
the electricity is generated by chemical action. 
When a storage battery is allowed to stand, local 
chemical action takes place between the plates 
and the acid without the development of any elec- 
tric energy which can be utilized, and it is neces- 
sary to re-charge it after a while. There is also 
a tendency of the plates to break up and ciumble 
after being used for some time, which has been 
found to be a serious objection to their use. No 
really practical form of storage battery has yet 
been introduced. 
M. S. IT., N. Y. — If a bullet is fired from a gun 
in a vertical direction will it return to the ground 
with the same velocity with which it started 'i 
Answer. — A bullet fired vertically from a gun 
will rise in the air with a constantly diminishing 
velocity, owing to the attraction of gravitation, 
until it comes to rest. It will then begin to fall 
with a constantly increasing velocity, owing to 
the same force, until it reaches tlie ground again. 
If the bullet was fired into a vacuum these attrac- 
tions would be equal, and it would return to the 
ground witli the same velocity with which it 
started ; but the friction of the air thiough which 
it passes tends to reduce its velocity during the 
entire journey. It would, therefore, reach the 
ground with a velocity much less than that with 
which it left the gun. 
A. 11. F., Montreal. — A recent writer in the Sci- 
ence News speaks of the combination of anti- 
mony and chlorine as a "combustion." Is not 
the term incorrect, and is not the term combustion 
only properly applied to processes of oxidation 
accompanied with light and heat? 
Answer. — lliere would appear to be no reason 
why the term "combustion" should not be ap- 
l51ied to all chemical reactions accompanied by 
light and heat, and we find it so defined by all the 
best authorities, including Watts and Roscoe. 
Practically, in ninety-nine cases out of a hundred 
combustion is caused by oxidation, and the few 
exceptions may well be included under the same 
term. 
E. J. H., Mass. — What is the composition of the 
wat°r in the so-called " petrifying brings," which 
apparently changes into stone any object over 
which it is allowed to flow. 
Answer. — The water of these springs contains 
carbonate of lime, or limestone, held in solution 
by an excess of carbonic acid gas. As the water 
evaporates, the carbonate of lime is deposited as a 
heavy, stony coating upon any object in contact 
witli it. Stalactites and stalagmites are formed 
in the same way. The process is simply one of 
incrustation and not a true petrifaction, as in the 
latter case the original particles of the petrified 
object are removed and icplaeed by those of the 
mineral substance dissolved in the petrifying so- 
lution. 
T. L. C, Minnesota. — I have recently exchanged 
my clieap photographic objective for a fine im- 
ported lens, but I caunot take as good pictures 
now as formerly; the negatives are flat and with 
little contrast. What is tlie matter? 
Answer. — The trouble is undoubtedly in over- 
exposure of the plates. 'I'lie new lens works so 
much quicker than the old one that an exposure 
which would give a satisfactory picture with the 
latter is nuich too long for the superior light- 
gathering power of the former. Try reducing the 
time till the results are satisfactory. The proper 
time of exposure is all important in photography, 
but it can only be learned by practice, and varies 
constantly with ditterent plates, lenses, chemicals, 
times, and seasous. 
LITERARY NOTES. 
Catalogue of Minerals and Hynonyms, by T. Eg- 
leston. Ph. D. John Wiley & Sons, New Yoi-k. 
Price, .$2.50. 
This valuable work contains a complete list of 
all known mineral species, with cross references 
to all the synonymous terms by which they aie 
known, both in English and foreign languages. 
Mineralogists and those having charge of collec- 
tions of minerals w ill find it exceedinglv useful. 
Principles of A(jricnlture fur Common Schools, by 
J. O. Winslow, A. M. "Price, 60 cents. 
First Lessons in Arithmetic, by Andrew .1. Rieboft'. 
Price, 36 cents. 
Plane and Solid (leometry, by Scth T. Stewart. 
Price, $1.12. 
The above text-books, published by the Ameri- 
can Book Company, of New York, are fully up to 
the standard of all works issued by this enter- 
prising house. The elementary text-i)ook on agri- 
culture is a novelty in educational works, but a 
most valuable one, as a knowledge of the princi- 
ples of agriculture — which simply means a know I- 
edge of the natural laws and principles which 
underlie rural life and rural pursuits — is not only 
important for tlios(! who are actually engaged in 
the pursuits of agricidtnre. but may in general be 
regarded as an important element in the education 
of the young. The mathematical works are also 
written in conformity to the latest mathematical 
and educational theories, .and the whole series is 
wortliy the attention of teachers and school com- 
mittees. 
Postal Dictionary. A manual of postage rates, and 
information upon every postal sul>ject which 
concerns all who use the mails. Sixth edition, 
revised to date. E. St. John, 5 Beekman street, 
New York. Price, 15 cents. 
This little dictionary is likely to be of great and 
constant service to all who make much use of the 
mails. The uinety-four pages contain a great 
amount of information, very well arranged, 
knowledge of which should prevent most of the 
delays and losses in the mails. 
Pamphlets, etc., received : Description of the 
Marine Biological Laboratories and Aquaria of the 
University of Pennsylvania, Sea Isle City, N. J. ; 
Trichina Spiralis, by Dr. H. M. Whelpley, St. 
Louis, Mo. ; Enucleation of the Eyeball, by J. Ho- 
bart Egbert, M. D., price, 35 cents, of Hampshire 
Publishing Company, Southampton, Mass. ; Sul- 
phuring or Bleaching Dried Fruit, by .1. W. Smith, 
M. D.. Charles City, Iowa; and the Thirteenth 
Annual Report of the Bhode Island State Board 
of Health. 
