Evening star., 1909-05-29

armored motor car. 1t carries In the rear
q revolving cupola occupied by two men.
one to manipulate the cupola and the other
the gun. The chauffeur has also an ar
mored- screen behind which he can rem
der himself and his driving gear invis-
ible. The machine weighs little over
two tons. is OF 35 horsepower and can
travel p miles an hour. 1t was found
quite capable of ascending to all parts OF
Port Valerien, of using the toughest coun-
try roads and Of clearing the widest and
deepest bitches.
The Rustling of Iron.-An American ply
sicist, DR.. Cushman, announces that the
rustling of iron is really due to electricity.
He has found that the first attack on the
metal is made by hydrogen In the form
of exceedingly small particles, but not. as
the text books have taught us, by oxy-
gen. This Is in agreement with the mod
ern theory that many substances, when
they are dissolved in water, are dissoci-
smaller even than atoms. all carrying
electrical charges. Even pure water con-
tains certain number of these. Acid
impurities multiply the hydrogen ions and
strengthen them in their corrosive effect
upon iron. The action is purely electric,
and involves an exchange of the electric
relations between the hydrogen and the
iron. BY immersing the iron in concen-
trated solution of chronic acid and then
washing and wiping 1t. says DR.. Cush-
man. the metal is rendered passive, so
that 1t becomes capable of resisting cleo
tro-chemical attack. This. IL true, re-
marks the Circle, means that a method
has at last been found for protecting
structural iron work and machinery.
A new motor-gas "alkoethine' is a mix
ture of air. alcohol. vapor and acety-
lene, resulting from the spraying of dilute
alcohol over calcium carbide. 1t proves
to be a cheaper fuel than gasoline and
the necessary apparatus for producing 1t
can be adapted to any high-speed gaso-
line motor
The limit of mining operations in Eng
land is 1900 feet.
In eleven years the coal output of ia
pan has increased from 2OO 900 tons an
nually to 100000
Too much food, exercise and education
have serious effects on the memory.
The elephant has only eight teeth.
The total cost Of the buildings erected
In the principal cities of the United States
In 1907 was 1851 ,078 2S6, a net decrease OF
$l7,634, 1888 from the figures of 1905. but an
increase over those for any previous year.
The unit cost OF building, however, in
creased In the past year, for there were
some 1s4.055 permits issued In 1907. as
against 1S1,174 in 1906. In the cities
showing decrease in building New York
takes the lead. with falling of Of Sal
5Sl.9 1882, or 1884 per cent.
A combination barrow and concrete
mixer Is now made for small jobs and
repair work, and saves much time in the
manipulation and transportation Of the
materials required. The barrow, loaded
with the sand, cement and water, is
wheeled up to a small cradle arrange
ment, where cover fits down over the
barrow body, and at the same time a
number of blades sink into the mass
The mass Is then churned by the blades
until It has become thoroughly mixed,
which requires but few minutes, on
account OF the great efficiency of the
blades. The turning may be done by
hand-power. but where ii is convenient
this work may be done by steam or cleo
trical power. A device of this kind is
also designed for use on farms and other
places OF a like character where concrete
is becoming very popular because of its
where 1t Is largely used as a substitute
for wood in great variety of work.
An English railway official at Burton
upOn-Trent has devised an emergency
rail groove brake, which has been used
with great success on the municipal line
of which he Is an employe. This is an
emergency mechanical brake additional
equipment on the car. 1t Is instantaneous
in action and has no graduatons; when
applied it must be at maximum brakng
effort, No expenditure of power or sand
Is required for its application. A maliea-
BILE iron bracket Is attached to the track
frame. inside the wheel base and close
to coach wheel 1ange. This bracket sup
ports through compression spring and
pair Of links. malleable iron bleck ear
rying a renewable manganese steel skid
shoe Of q shape to conform to the rail
groove, The brake is held away from
the track by steel wire or cable, so that
when this is released the compressed
spring forces the skid bar into the groove.
The brake block also engages the wheel
fange and is forced downward with addi-
uonal pressure. Only the brakes on the
rear wheels are released.
Mr.. e. l.. Rinmann of the University
of Upsala claims to have discovered a
new process for the electrical extraction
of aluminium from blue clay by which
the cost of production is reduced to about
one-auarter Of the present rate.
The United States government MAIN
tains fifty-seven wireless telegraph sta
tions and has ninety-six vessels fitted. out
with such facilities. list of the land
stations is as follows:
FIT. Levett. Me. Cuebra w
Cape Elizabeth Me. Colon Panama
Portsmouth, n. II. Farallone Island,