Manchester Democrat. [volume] (Manchester, Iowa) 1875-1930, 1905-11-01
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An Interesting hygrometer is made
ny dipping strip of calico In solu
tlon of one part of cobalt chloride
seventy-fve of nickel oxide and twenty
or gelatine in two hundred of water.
The strip is green in fine weather
fading as moisture appears.
An Italian scientist has invented n
novel substitute for irrigation. He
uses the fruit Of the Barbary nopal
fig tree which bears figs that are
excellent reservoirs of moisture. In
the spring the scientist digs ditch
about the foot of the tree he desires
to protect from the coming drought
and this ditch is filed with figs cut
Into thick pieces. A dense layer is
made and beaten down. The mucIlag.
nous pulp. covered with earth, stores
up much moisture, which it gives off
gradually, watering the tree sometimes
for as long period as four months.
The light of the freely is believed
to have an efficiency of virtually 100
per cent of the energy expended,
whereas recent tests indicate that the
light efficiency of the ordinary mean
descent lamp is only &c per cent;
the rest Of the energy is expended In
producing heat which is not needed
inventors do not yet despair of sue
cess In initiating the firefy's economl
cal method of producing an illumina-
ton. In recent paper f. G. Caldwell
says that 1t Is well within the range
of possibility that we may see the
transmission of light-producing energy
entirely done away with, and a return
made to some form of portable lamp,
consuming an exceedingly small
amount of material, and producing a
Cold" or flrehy-like, light.
II the earth, says Prof. e. Ruther.
ford, were supposed to have been COM
posed, fnitially, of pure radium, the
activity 10000 years later would not
be greater than the activity observed
In pitchblende to-day. But, since there
is no doubt that the earth's age vastly
exceeds 10000 years, it is necessary.
In order to account for the existence of
radium ut all in the earth, to suppose
that 1t is continuously produced from
some other substance. At the present
time 1t seems most probable that ura-
mum Is this parent substance. The
observed activity in good specimen
of pitchblende is about what should
be expected If the uranium contained
in it spontaneously breaks up into
radium. Radium itself Is continuously
transformed into an emanation which,
in turn, is changed into other types
of matter, and there is no evidence
that the process is reversible.
A portable electric plant for fixing
rails and packing sleepers, the inven-
ton Of A. Collet, of Paris, is in use
on several French railways. The APP
paratus runs on wheels adaptable for
ordinary roads or railway tracks, and
includes twenty-five horse power en-
CINE, which is coupled by belt to the
dynamo that generates electric cur
rent. Steam Is supplied by vertical
tubular boiler of capacity of only
15h gallons. The engine being In
place, a copper circuit is carried along
the permanent way three-fifths Of a
mile on folding ladders, and con-
tnuous current Of 800 volts is led to
the track-laying machines. With two
wood screw machines on small truck,
four men lay 1871 yards of track in
ten minutes, setting two hundred
screws, this being seven times the
rate by hand. The sleeper-packing
tool gives four hundred strokes per
minute, and enables six men to pack n
sleeper in broken stone in one minute
or in sand in thirty-fve seconds.