The Democratic press. [volume] (Ravenna, O. [Ohio]) 1868-1901, 1881-06-02
SCIENTIFIC AND USEFUL,

1t is considered by Nj. Perisse that i
is almost certain that the ancient Egvp
tians and Ph9nicians used steel, If, in
deed, they did not make it. 49, tft''f
The Belgium Telephone Company
have made arrangements so that any OF
the subscribers leaving word any even
ing. may be awakened at any hour The
next morning by means of powerful
alarm. 'it - ,-ad
DR.. w. Reigler says that the quantity
of rain water which finds its way to
the ground along the trunks of trees is
very considerable. but that some kinds
of trees discharge this function better
than others. s-.,3 ..,f..,
1t is maintained by Prof E. Wool
ney than soil heaped up around plants
has, during the day. a higher tempera-
ture than earth not so treated. During
the night the hilled4 earth becomes
colder The explanation advanced is
that earth which is heaped up around
plants dries much more rapidly than
level soil. -e t---ti .ts.;.
From the success which has already
attended the introduction of electric
clocks, and their evident utility for
railroad, postoflice, and telegraphic
offices, DR.. M. Hipp predicts that in
few years every town of any Importance
will have its time regulated by cleo
tricity, just as it has its light by night
supplied now by means of illuminating
gas.
Writing about some phenomena of
optics, Nj. Treve mentions the fact that
the flame of q lamp appears brighter,
and that an upright post, shaft, or mast
is seen more distinctly through verti-
fhon hD, al al; l,,,% =
house, a landscape, or the disk of the
the slit is horizontal. Photographs pre-
sent more or less clear definition accord
ing as the light passes from the kind of
odject exposed to the sensitive plate
through an opening or slit of horizon-
tai or vertical nature. The results are
ascribed to the action of ditfused light.
A calculation has been made by some
arithmeticians of the extents to which
steampower has been developed. En-
gland derives from her wealth of coal
1000. .00O-hOrse power; the United
States, 7,500,O 900; Germany, 1000. 600;
France, 100000; Austria, 800, 0O0.,.
These figures do not. include the loco
motive which, taking the num-
ber of locomotives in both hemispheres
to be more than 105, 900. and the mile
age 222, 900 miles-must have 80, 900, -
000-horse power All the machines
and engines worked by, steam in the
world is estimated at sc. 900, 600 horse
power. Each horsepower is equal st I
least TO the strength of 10 men. and the |
steam power of the globe represents
daily working power of 100000, 900
men. -, .
DR.. Lenz has found that Timbuctoo
has now only, 10000 inhabitants, and
that many of its brick-built houses
have fallen in decay. But the town
yet contains many schools and rich
libraries, besides not a few learned men |
capable of holding extremely interest," |
ng dialectic discussions, especially on
doctrines of the Koran. The old canals
which formerly connected the place
With the Niger, distant only about six
niles, are now merely series of lakes.
His notes regarding the Sahara are of
The Great DESERT is in
10 part below sea-level, and is plateau
more than 900 feet above tide-water.
Iere and there are hills of granite,
plains of sand, very shallow lakes,
md patches of great fertility, and there
re very few beasts of prey. The Sahara
# the boyhood of still young men is
apidly losing its romance of terror n
nder the influence of the more recent
ccounts of actual exploration. rsall