Essex County herald. [volume] (Guildhall, Vt.) 1873-1964, 1886-12-24
up the pistols and took the ''calico
frockn instead.-Neu York Mercury.
SCIENTIFIC AND INDUSTRIAL.


The official Investigations made in
Prussia relative to the causes of mine ex-
plosions show, among other things, that
many explosions attributed to fire damp,
or outbursts of gas, are really due to the
| fine coal dust in the mines.
The power for the electric railroad at
Toronto, Canada, costs only 81 a day.
The equipment for l 1-2 miles of road
cost $1,000; the receipts are $500 a
month, and after all expenses are paid a
profit of IS per cent. is realized.
Cold-air machinery has been success
fully used in the construction of tun-
mel at Stockholm by freezing the gravel
before the excavation and keeping it in
that condition until the lining was in po-
sition. In this way several large build
ing have been undermined.
OF interest to engineers is a tell-tale
paint, the invention of an Englishman.
If the bearings of the engine are covered
with this paint, the abnormal color of
which is q brilliant red, and such bear
ings run hot, the paint will darken in
color, until at 1902 Fahrenheit it is quite
brown. AS the paint cools it recoveIs Its
original hue.
A Hungarian engineer has been using
dynamite at Pesth for driving piles. He
placed an iron plate, fifteen inches in di-
ameter and three and three-quarter
inches thick, in perfectly horizontal
position on the pile to be driven. A
dynamite cartridge in the form of disk.
pnnfoininn Lol
ounces of dynamite, it is placed on the
iron plate and explo led by electricity.
Nearly all kinds o. minerals are album
dant in Japan, but mining and metal
lurgy, although practiced to some extent
for centuries, do not take the prominence
that would be expected, when we re-
member that some of the most exquisite
specimens of hammered iron and bronze
work to be found in important collec-
tons to day, are the production of Japan
csc artisans of one thousand years ago.
The government, however, is extending
aid TO these and to many other indus.
tries, in a spirit as intelligent as it is
liberal.
BY new process of toughening wood,
it is claimed that tho effect produced
upon whitewood is such that u cold
chiscl is required in order to split it
this result being accomplished by spc-
cial method of stcaming the timber and
submitting it to end pressure. By this
means the cells and tibres are compressed
into one compact mass, and some of the
timber, commonly considered unfit for
use in such work as carriage building,
for example, can be made valuable by
this means as a substitute for ash, hick-
DRY, etc. This method is applicable, of
course, only to wood in comparatively
small quantities or sizes.
An English naturalist remarks that it
is a sad reflection that, while the turbot
lays ID, 900, 900 eggs, not more than one,
on an average, evec lives to reach ma
turty. In fish, generally, it takes yearly
at least 100, 600 eggs for each individual
to keep up the average of its species. In
frogs and amphibians few hundreds arc
amply sufficient. Reptiles often lay a
much smaller number. lin birds, which
hatch their own eggs and feed their
young, from two to ten eggs per annum
are quite sufficient to replenish the earth.
Among mammals, three or four at a
birth is a rare number, and many of the
larger sorts produce one calf or foal at
time only. In the human race at large,
a total of five or six children for each
married couple during whole lifetime
makes up sufficiently for infant mortality
and all other sources of loss, though
among savages far higher rate is usual
ly necessary. In England an average of
four and half children per family suf-
fees to keep the population stationary.