The citizen. (Honesdale, Pa.) 1908-1914, 1911-12-20
Scientific Miscellany.
Magnetic Strength-Testing- Edible
Earth Mining-Reinforce Paving
Feed in Horse EvoIution--Milk
That Keeps.

A novel electromagnetic tensile
test apparatus Is an engineering de-
vice for showing the effect upon ma
terials of repeatedly loading and un-
loading. It consists of a frame of
four fixed parallel side bars, a fixed
top head in which one end of the
test piece is fastened, fixed bottom
head carrying two upward projecting
pole pieces surrounded by two excit-
ing coils, and movable head sliding
between the side bars and gripping
the lower end of the test piece. In
normal position, the movable head
is close to the end faces of the pole
pieces, serving as an armature to the
magnet. When an alternating cur
rent is sent through the magnet
winding, the armature and test piece
are subjected to a rapid succession of
pulls and the pulling force can be
determined from the supply voltage
and the air gap between pole pieces
and armature. In machine already
built pull of 220 pounds is obtain
ed with a current of 100 volts. The
load may be applied many times in a
short period, 50-cycle current Civ
ing 100 pulls a second, making 81
$4,000 loadings in "a hours.
Geophagy, or earth-eating, is COM
mon in many places, but it seems to
have reached a unique development
in the French Sudan, as described by
Henry Hubert, French author.
Though food is abundant, the dirt
a kind of clay-is obtained by reg
ular mining. The clay beds are of
varying thickness, and, as the deep
er layers are preferred, galleries are
dug to reach the choicest material.
A single native often eats pounds
or more in day.
The influence of soft bread on chill
drens teeth has been investigated in
Germany. At Kotzling, Bavaria, SO
per cent. of those eating hard bread
had diseased teeth; so per cent. of
those eating both hard and soft; and
10.5 of those eating only soft bread.
At Ihringen, Baden, the percentage
rose from 12.4 in 1894, when only
hard bread was used, to 209 in
1901, when the bread was mostly
soft.
The reinforced macadam of Quiet,
a French engineer, is new road ma
terial that is claimed to have given
superior results in his tests of the
last year or two. 1t is made in
plates of various sizes, and consists
of a bottom layer of cement enclos-
ing the strengthening pieces of fiat
and circular iron, and top layer OF
broken stone pressed into the ce-
ment Formed into plates of moder-
ate thickness % inches long and 19
wide, the pavement readily support
ed an evenly distributed load of 30
tons or load of tons concentrat-
ed at one point. The surface has
been found very resistant to the wear
of heavy traffic, and its smoothness
giving a striking contrast to stone
pavement-is special advantage.
In places where the plates are too
expensive to use over the entire
width of the roadway, it is recon-
mended that narrow track be laid
to receive the wheels of vehicles.
A kind of wild clover called "zul-
Ia" found only in the Province of
Cadiz, has been proclaimed by
Spanish horse dealer as the finest
feed known for horses. The plant
grows luxuriantly in chalky or clayey
soil, seems to thrive best wild and is
never cultivated, reaches a height of
three or four feet, and sometimes
yields Is tons or more to the acre.
1t is cut and dried like hay. A re-
cent tendency in Spain has been to
use the Spanish-English hackney as
draft animals, but the Spanish sad
dle-horse is asserted to have retain
ed its supremacy for speed, endur-
ance and tenacity of life. These
high qualities are attributed to the
feed. 1t is declared, moreover, that
any class of animals may be improv-
ed by introduction to the favored
region, and that in the Zulla locality
they will in two generations acquire
the extraordinary toughness and en-
durance.
The success of powdered milk may
be of far-reaching Importance, as it
connects all sources of milk supply
with the worlds markets. 1t is de-
veloping a great industry in New
Zealand, which provided large
amount for Shackleton's expedition
and is to supply two tons for the ex-
pedition of DR.. Mawson. Advantag-
es are claimed over condensed milk.
1t excels in keeping qualities and nu-
tritive value, and is specially adapt
ed for infants food by its thorough
sterilization and close resemblance
to human milk.
Photographing through colored
screens is the new method of study
ing Mars that has been undertaken
by Tiqhoff at the Pulkova observa-
tory. Four different screens were
used-transmitting respectively red,
red and orange, orange and yellow,
and greenland in the 30-inch equa-
torial telescope they produced good
photographs of very small size. The
red and the green filters gave strik-
ingly different results. On the
plates that were exposed under the
red, the continents are much brighter
than the south polar cap, while the
seas are very dark and the canals are
best seen; and the pictures that were
taken under the green show the
south polar cap as the brightest OBJ
ject, and the seas are grayish. A
study of the polar cap has made it
appear greenish instead of white.
The interesting conclusion has been
reached that at the time the photo
graphs were made the cap was ice
instead of snow, and this view has
been confirmed by experiments on the
ah ahunrnfinn Of ian and In