The Republican. [volume] (Oakland, Md.) 1877-current, 1889-07-13
SCIENCE AND INDUSTRY.


Tin and glass have found rival in
paper as a material for making kerO-
sene oil cans. The latter, it is claimed,
will not rust and leak like tin or crack
like glass.
Experiments in welding wire rope
by the electrical process show that the
strength of the finished welding is
within eighteen per cent. of the nor
NAL strength of the cable.
-"Linotypes" are Photographic
prints mounted on linen. Washes of
color are applied to the back of the
prints, so that they can be used as col
ored trarsparencies with excellent eff
feet.
In Paris the saccharine or sugar
made from coal has been unanimously
condemned by the medical profess on,
because it seriously troubles digestion.
In consequence of their recommends
ton a law has been enacted prohibit
ing the use Of coal sugar as an article
of food.
"A new mat which acts as a foot
scraper without retaining the dirt on its
surface, and which is readily cleaned, is
made of flexible wood mating. Strips
of clear white hard maple, straight
grained and we'll seasoned, are con-
nected by means of galvanized iron
wire, with rubber tube between them,
and the result is very durable and
flexible matt
1t appears that the lover of mush-
rooms is in danger not only from a
poisonous species, but from poison
GUS state of the edible kinds. In
Switzerland several cases of poisoning
from dried mushroom have led to the
conclusion that poisonous ptomaine-
like substances may develop in edi-
BILE mushrooms by slight putrefactive
changes.
"A new road-sweeping machine has
been tried in London. 1t can be easily
attached to any cart and worked by an
experienced hand. Travelling at the
rate of three miles an hour, the ma
chine sweeps through twelve hundred
square feet per minute of any road, and
places the mud in the cart behind with
out noise or splash.
"A plan for rendering paper as
tough as wood or leather, it is said,
has been recently introduced on the
continent. 1t consists in mixing chic
ride of zinc with the pulp in the course
of manufacture. 1t has been found
that the greater the degree of concen-
tration of the zinc solution the greater
will be the toughness of the paper. 1t
can be used for making boxes, combs,
for roofing, and even for making boats.
Whilst the growing use of steel as
an engineering material testifies un-
mistakably to its superior suitability
for general purposes, yet there are
situations where it appears to be re-
jected in favor of iron. and these in
stances seem lately to have been on
the increase. The greater liability of
steel to corrosion is in many cases the
cause of this preference for the older
metal. especially in boilers where the
feed-water is bad.
"A SlinplS SGONe lOF WdrHlluS rOOnS
by means of solar heat has been con-
rived by Prof. E. S. Morse. 1t con-
sists of shallow box, having a bottom
of corrugated iron and a glass top.
This device is placed outside the build
ing where the sun can shine directly
into it. The rays pass through the
glass and are absorbed by the metal,
heating it to high temperature and
warming the air of the box. The air,
which on sunny days rises to ninety de-
grees F., is conveyed into the room to
be heated.
Professor Hartley, of London, has
been trying to find out why the sky is
blue. His experiments show that the
color arises from the action of ozone
upon the rays OF light. The result of
his examination of ozonized air goes to
prove that it is impossible for rays of
light to pass through so little as five
miles of air without the rays being col
ored sl1y-blue by the ozone commonly
present, and ''that the blue of objects
viewed on a clear day at greater dis
tances up to thirty-tive or fifty miles
must be almost entirely the blueness of
ozone in the air.