Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1875-08-05
MECHANICAL AND SCIENTIFIC

To waterproof fishing. Lines ann,r
mixture OF two parts boiled linsead' !,
and one part good size; expose to the OIL vi
and dry. 1o air
The preparation for blackinp ,ho
Drass-w0rk OF lenses, etc. is made as sn o
lows: -Four drains of bichlorid of nio o.'
mum and one grain of nitrate of SIT a'-
and six ounces of water. The bras. , WI
Is to be made quite clean and the prenasa
ZION must be applied with camej,s .ha;.
pencil. When the right depth il Aa -.
tanned wash with clean water dry o a"
finish with black lead-Miainq and p"
cheering Journal. 1-~
Mr.. George W. Blunt, the wellknou,
nautical expert Of New York CITY CIV
the following simple mode for rlnnina
meridian line: Take piece of hoa,d
or any similar material, and describe ON !,
a number of concentric circles. p,aoo
this in the sun; over the center HANG
plummet; observe the shortest shadow fro,"
the plummet the SUN Will be then on tba
meridian; draw line to the center of III"
circle and that will be the true merdiar
line. This will do to mark the apnaran.
time or to correct the compass of variation
An English engineer, in an article on
bridge building, says that the foundation
of each pier should be one undivided
structure, and should not be broken into
separate parts as is the case where cvlin,
ders are used and that, besides the resist
ance due to the horizontal area of ,bo
foundation, it should embrace the add.
tional resistance afforded by the friction
due to the vertical surface of the pile and
this, short of founding on rock itself
presents the most solid resisting mass that
can be found. The foundation being a
part of the structure which resists the
weight of the superstructure, the higher
the horizontal place of the resisting mass
is, the less is the weight ofthe superstruct.
ure upon it
"A company is said to have recently
been formed in Paris for the purpose Of
testing the non-conducting property of
cork. A number of steam pipes at several
important establishments had been covered
with cork and it is said that, after stand.
| ing some eighteen months, the covering
remains intact, and is as perfect non.
conductor as on the day it was laid. Al
| though the durability of cork had been
proved before, in the case of buoys, which
| are partly immersed and partly exposed to
| the weather, its ability to stand such high
temperatures as those ofsurfaces intensely
heated by steam had not before been
shown. The lightness of cork, the readi-
ness with which it yields 80 as to surround
cylinders or pipes, the facility with which
it is put in It's place, taken down and put
up again, in the case OF the inspection or
repairs of boiler or steam-pipe, together
with the fact that its non-conducting
power effects a great saving Of fuel, are
regarded by engineers as greatly in its
favor for the outer coating of steam
vessels.
DR.. J. Gibbons Hunt, Chairman Of
the Microscopical Section of the Philadel.
phia Academy of Natural Sciences, has,
by recent Investigations, determined the
true cause of the fire ght that for many
years has affected pear-trees in the United
States. 1t is, as has been suspected the
work OF fungus. The plant first germi-
mates on the outside of thu bark, causing
immediate changes in the cells, filling
their naturally transparent contents with
dark pigment granules. The cambium
cells are soon affected in the same way, in
a complete circle around the stem. From
the cambium layer the fungus travels, by
the medullary rays, to the interior of the
stem, leaving destruction in its path, In
the heart of the stem the spores are deyel-
oped. The plant is exceedingly minute,
being visible only under magnifying
power of 500 diameters. Its name has not
yet been determined, nor whether there is
any predisposing cause for its occurrence.
It's external effect upon a branch is like
that produced by a fire. The leaves, in
an apparent condition of health, suddenly
shrivel and turn brown, as though scorched
with flames