The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1900-08-25

by Acknowledgements Smoke Pre-
vention-Dissolved Acetylene-Has the
Earth Tail2-A Railway Train as
Bird-Trap-New Elements in the Sun
Domestication and Evolution = Indu-
ence of Colors.
The water-supply plants of the United States
are stated by Mr.. Allen HaZen to have reached
$500 in 1899, about three-fourths of them being
operated by pumping. Only about one-tenth OF
the cities have filtered water supplies, although
fever is generally recognized Mr. Hazen favors
slow filtration through sand-beds, but finds that
filters of this kind are used in the United States
only by cities of an aggregate population OF
100000 but in England by cities of 1020O,OOO in
habitants. and by total population in the world
of 2l,400,O00. Mechanical filters are employed
by an aggregate population of nearly 1,6OO,OU0
in the United States and Canada. although prac-
tically unused in other countries.
The commercial use Of the electric arc in the
culture of Easter lilies is shown by Mr.. M. q.
Kains to be quite practicable, but he finds that
this light should not be used until the lily buds
are an inch long and that it should then be
passed through glass to screen out the ultra
violet rays. In the experiments CONSIDERED,
dark brown burn appeared on the plants under
the naked light. The light was continued nightly
for four months, giving plants that were taller
with shorter-iived flowers than those grown in
the dark.
More perfect combustion in furnaces is Sc
cured by Mr.. Paul Schlicht by novel means.
He has discovered that on properly introducing
an air current into a chimney, it takes a course
opposite to that Of the hot gases, and its oxygen
reaches the centre of the fire in a heated condi-
ton favorable for completely uniting with the
fuel.
Clinker from the refuse Instructors at Brad
ford, Eng, which lately caused considerable
expense, is now probably used for mortar ana
concrete, proving serviceable for reservoirs, etc.,
when mixed with cement.
Aoatvlana hos failed fh1,s far to realize all that
was expected from it on account of the lack of
a really practical small generator, and its de-
livery under compression in cylinders is still
less practicable on account of the great risk of
explosion. 1t Is believed in France that the
factory results. These experimenters have
found that acetone will dissolve "a times its vol
ume of the gas at ordinary temperature and
pressure, and that this could be increased to
more than 1000 volumes If a temperature of 800
G. below zero could be maintained. or to 240 vol
umes at ordinary temperatures under pres
sure of 10 atmospheres. Storage in acetone So
luton under pressure is therefore the plan
under trial. Still greater safety is ensured by
Teservoip as to eectmaIiy check the gas in It
from being ignited from the burners.
80
Astronomers are bringing forward numerous
theories to explain the Gegenschein, the bright
patch that sometimes CLOVIS mysteriously in the
sky at midnight The light occurs near the
ecliptic: but usually two or three degrees re- 2.
quite generally believed to have no connection
with the earth's atmosphere. A plausible.
though not wholly satisfactory, view is that 1t is
a reflection from the ring of fragments to which
the known asteroids belong. Another sugges-
ton is that it is a comet-like tail of hydrogen
and helium streaming away from the earth in q
direction, opposite to the sun, while many as
tronomers are inclined to connect the phenOme-
non with the meteoric ring producing the 70
diacal light.
The curious behavior of a falcon has been
noticed by travellers on a railway passing
"a
bird always accompanied the fast train of the
line, paying no attention to other trains, and
the ground on each side. 1t was found that
the air eddy set up by the rushing cars drew in
the smaller birds, which were thus made easy
victims of the cunning hawk.
There are now 20 crematories in Europe and
America, of which 81 are in Italy, 20 in the
United States, in Germany. and 4 in England.
Paris had 4,5l3 incinerations last year.
Helium was known to exist in the sun, through
certain bright lines seen by Lockyer in the solar
spectrum, long before Ramsay isolated it in 1895,
thus showing It to be also terrestrial element.
This gas has about twice the density of hydro
gen. Certain other colored lines were assigned
by Lockyer to another element, which he called
.'cOronum." but this has not yet been isolated,
but an Italian spectrOscopist has proven its ex-
istence on earth by detecting its lines in gases
from the crater of Vesuvius. Other lines still
have now attracted the attention of physicists
studying the solar spectrum. These are assigned
to two other hypothetical elements, which are
named ana 0eDutuTn, ana, WnaU Is
believed, from the position of these substances
in the suns atmosphere that they must be
lighter than hydrogen. The actual discovery of
a body lighter than hydrogen would revolution
ize our views of molecular weights.
-.
Exhibits now being arranged at the South
Kensngton Museum are designed to give
practical illustration of evolution by showing
the changes man has wrought by artificial breed
ing in horses, cattle. sheep, dogs, cats, rabbits
Birds fishes. bees, silk-mOths, and other species.
Prepared skeletons will show that the changes
which are grouped fancy breeds that have
sprung from it some jungle fowl, the originals
of our breeds of poultry. together with some of
the latter; and both wild and cage-b bred cana
ries.
AFs
SilkwOrms, in FlammariOn's experiments,
have attained their maximum production of
silk in white light, the next in the purple of the
red end of the spectrum. and a minimum in
blue light. In blue rays the males produced
reach SO per cent. The red rays favor the pro-
duction of females. and also their fertility,
twice as many eggs being laid as in blue light
-
The lessening of accidents among working
electricians is sought by the Society of Agricul-
tural Industry and Commerce of Milan, which
offers gold medal to the person of any nation
who makes known the best method of protec-