The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1906-09-29

post from Telephone Wire6-Tne suns
ders-vsn,shinr T,etters-New Magnet
Wire-Color Measuring-A Diminutive
Engine.
Directing wireless telegraph messages by
parabolic refectors of metal plates or wires has
failed on account of the great loss of energy.
In the new method of Prof. F. Braun, of Stras-
burg, three or more aerial wires are placed on
masts at equal distances of a few yards from the
transmitting station. and the oscillations are set
up in one wire slightly in advance or behind
those Of the other wires. The effect is an in
tensihcation Of the waves in the direction Of the
leading discharge, with the production Of an
electrical shadow by wave interference behind
1t. The difficulty has seemed to be to give the
slight difference of phase-amounting to about
one ten-millionth Of a second-with precision,
but It has been found possible to adjust the
difference to less than one two-hundred-mil-
lionth Of a second. With three wires, the mes
sages can be sent in any one Of six directions.
~
A curious telephone complaint has developed
in Cape Colony. White streaks appeared on an
iron roof under two wires and it was demanded
that the wire be removed and a new roof placed
on the building. One If the many theories was
that the deposit was salt collected by the wires
lEOu1 Tue sea Wlulbs 1uNcottSntiOus uOWCtcEs
showed that the roof was intact and that the
powder was nearly pure silica. Fine sand blown
upon the damp wires had afterward fallen to the
roof and adhered.
The sun proves to be undergoing a continual
change of shape. From measurements at Got
tingen during thirteen years, DR.. C. L. Poor
finds that the ratio between the polar and equa-
toral radii has varied considerably, and that the
variation takes place in a period closely corre-
spending to that Of the sun-spots.
s+s
Good photographs of the interior of the eye
have been much desired by oculists. In his
efforts to supply the need. DR.. Walther Thorner,
of Berlin, first photographed cats eyes, which
are much lighter than human eyes, but good
pictures of the latter are now obtained by means
of the improved apparatus which has resulted
from his experiments. The back of the eye is
carefully focused on the Photographic plate
with a soft light. The camera is opened by
special lever, and the eye is lighted up for
moment by fiash-light composition ignited by
spark from storage battery. The pictures
show distinctly the differences between healthy
and unsound eyes, making it possible to watch
the progress of disease.
81
s. Jambunathan has lately recorded the finding
in southern India of species of Stegodyphus
that builds spoDgy nests with outlying webs,
each nest being occupied by 40 to 100 spiders,
with q large excess of females. Sometimes five
or six nests are clustered together. The spiders
not only live and work together. but they share
with one another any prey that may be captured,
and some even show maternal affection ap-
preaching self-sacrihce. 1t appears that there
are other social species Of the same genus, the
first known having been reported from South
Africa.
Disappearing paper is French novelty. Ordi-
nary paper is first stepped in sulphuric acid,
diluted according to the intended durability, and
is then dried and glazed, the acid being partially
neutralized by ammonia vapor. The material is
adopted for temporary use. Sooner or later it
falls TO pieces, however, and it is recommended
to those whose correspondents forget to burn
their letters.
Electric waves follow the earth's curvature,
explains Erskine- Murray, Scotch engineer,
because a conducting layer high in air keeps
them from spreading into space, practically
causing them to travel between two parallel
conducting planes.
new insulated wire, intended to replace
silk-covered or cotton-covered wires for cleo
tromagnets for small currents, is being produced
in Berlin, and has quite remarkable properties.
The coating material. giving continuous cover
ing. essentially betra-acetic cellulose. 1t is
applied in numerous coats by special machine,
is both flexible and durable has great elasticity
and solidity, is moisture proof, and is not af-
fected by temperatures up to 3OOo F. Its insula-
ton resistance is so high that thickness of
000OS inch is broken down only by tension of
1900 volts. Wires ranging in size from 00O28 to
COOS inch are made, and coil of given size COD
tains much more wire than the ordinary coil
the coating being so much thinner than the
double triple silk or cotton with the additional
layer shellac.
An attempt at cumulative measurement
Of color, designed to show just how red or
how blue anything may be. has been made
by Joseph w. Lovibond, who has published q
book on the subject in London. By the super
position of glass standard color-scales, in q
special instrument for excluding all extraDeous
light, the number of units of red and yellow-or
any other cOmbination-necessaryt to match q
given color can be determined The glass test
slides have been prepared with great accuracy.
standard and invariable chemical solutions being
employed for the colors. with precautions as to
thickness and temperature, and the graduations
are equal.
The smallest triple expansion engine in the
world is claimed to be perfect working model
made by Robert Bunge, of New York. It
measures az inches across the bedplate and 3k
inches from the bottom of the bedplate to the
top of the cylinder covers. Even link reversing
motion is not omitted. With a steam pressure
of 100 pounds, the engine makes roo revolutions
per minute, and turns a screw * inches In
diameter by 7inches pitch. The three cylinders
are 5-16, 8 l6 and lO-16 inch in diameter. The
steam-pipe is y inch in diameter, and the ex-
haust is 3-l6 inch.
DIFFERENT opinions obtain with reference
to large and small dairy cows as economical
producers. While the difference is not marked,
it is unquestionably to some extent on the
side of large cows. At the Columbian Expo
sition in $685. which was one of the greatest
dairy contests ever held, Professor Woll, of
the Wisconsin Station, selected an equal num-
Der from one Of the sections and divided them
into three lots. designated small, medium and
large. The difference In cost of production
from these three was in favor of the large COWS,
cant that the worlds record breakers in milk
production were large cows. In the dairy test
at the Worlds Fair at St. Louis in 1904, the
twenty-five Jerseys in the test were much
larger than the average of the breed. At the
commencement of the contest they averaged
OIL pounds in weight. There are other rea-
sons, apart from the economy in milk pro-
duction, as to why the dairyman should aim
to breed large rather than small COWS. These
include the better stamina which they usually
possess and the reader sale which they
command.
A MINNESOTA paper says a supply of lumber
is more important to the State than the an
nual harvest of wheat. But how many of the
citizens of Minnesota ever give moments
thought to the principles of forestry by which
the present forest wealth can be judiciously
used and, at the same time, perpetuated?
LUCK OR no luck, it is easier to get along
L "a Al