Evening star. [volume] (Washington, D.C.) 1854-1972, 1909-07-03
SCIENCE NOTES.

In order to write book on the SUBJ
ject, which has recently appeared. Mr..
A. NJ. Worthington has devoted fourteen
years to the study of water splashes.
Minute investigation of the subject has
been not only possible, but of great in
terest. by the use of the modern camera.
by which series of pictures have been
made showing the splash at different
stages.
If a drop of milk is allowed to fall
from a height of fifteen inches into cup
of tea or coffee, to which milk has not
been added, observation shows us that
the white drop appears to penetrate a
short distance into the dark liquid and
then bounce out again. To find out
what really happens we have only to
inspect photographs of the drop as 1t
enters the liquid. 1t forms a hollow
bowl or crater six or eight times Its own
size Tin diameter). the milk flowing up
the steep sides in radial streams: surface
tension then pulls down the walls of the
crater. the milk streaming back from all
sides toward the center Of the crater,
from which a fountain rises, carrying
the reconstructed milk drop upon its sum-
NIT.
The latest development of Niagara
power Is the letting of contracts for about
800 miles Of transmission plant, by which
it Is proposed to serve the cities OF
Canada lying between Toronto and Lon
don. From Niagara Falls the line runs
fifty miles northwest 10 Dundas, where 1t
divides. one line of forty miles running to
Toronto and two others going in a west
erly direction to London The northern
branch is some 100 miles long and the
southern seventy-fire miles. From Lon
don there is fourteen-mile extension 10
st. Thomas. 1t is expected that the line
will eventually be extended to Windsor.
opposite Detroit. distance of some 100
miles. Three-phase current will be sup
piled by the Ontario Power Company, at
Niagara Falls, Canada, at 1000 volts
and 25 cycles, and will be stepped up
To 10000 volts for transmission. The
present capacity designed for is 10000
horsepower The transmission will be
made by means Of aluminium cable and
about 500 tons of this metal will be re-
quired for the purpose.
Experiments made by the officers of an
English railroad seem to demonStrate
that a waterproof cement may be made
from mixture of cement and clay. The
best results were obtained with cement
mixed with clay in proportions of one Of
clay to seven of cement. and the mixture
then used as the cement In Ii sand
mortar. Blocks of this mortar over eight
inches thick were impermeable. Speci-
mems six inches thick containing the same
materials, but mixed with per cent alum
solution, were also impermeable when
subjected to a forty-pound water pres
sure.
In some Of the coal mines Of Europe the
use of dynamite and powder has been
discarded for bringing down the coal, and
in their stead cartridges Of lime are made
use of. The cartridges contain calcium
oxide ground to powder, are from three to
four and one-half inches long, and have a
groove on one side in which half-inch
perforated tube is placed. The covering
| is of stout cloth, which also closes the
lower end Of the tube. while the other
end is fitted with tap. The cartridges
are inserted and tamped in the same man.
| ner as powder. and a small force pump
| Is then connected with the tap on the
tube by means of a short flexible pipe,
and water approximately equal in amount
to the quantity of lime Is forced through
the perforations into the cartridge. The
lime being thus saturated, tap Is closed
and steam is generated. which, with the
expansion of the lime itself, breaks down
the coal. -