The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1909-02-06
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.

Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
One Towns Peculiar Product--A New
Kind Of Motor-Cancer's Victims-Fast
Colors in Persian Rugs-The Light Cure
in Europe-A Heatless Lamp-Cooking
in Nickel-A Useful Artificial Leather
The Hour Glass for Accurate Time.
The quarrying of photographic stone is the
unique industry of the little German town OF
Solenhofen, about IS miles south of Nuremberg.
The material is a compact limestone of peculiar
texture and yellowish-gray color. hard blush
stones being the more valuable, and Consul H.
W. Harris. of Nuremberg, reports that the
known area containing these stones is not more
than or miles long by 3wide This little spot
has supplied the worlds photographic stones for
more than a century, while the supply promises
to last at least one or two centuries longer.
The deposit is in layers of half an inch to or
inches thick, extending from the surface to
depth of 100 feet or more. and much broken and
worthless rock is contained. Not more than
one-twelfth of the stone removed is marketable,
much of this having small value on account of
the small sizes of the clear pieces. The indus
all civilized countries, the leading buyers being
Germany. France, Italy and the United States,
in the order named.
The curious toy motor of Lucien Fourier,
lately awarded the grand prize at French ex-
hibition, seems at first to furnish energy from
nothing. Over q shallow vessel is mounted
horizontally an axle, with heavy loose-fttinR
rod passing at right angles through 1t, and the
ends of axle and rod are connected by cords OF
hemp. When liquid is poured into the vessel.
the two lower cords are soaked and shrink,
forcing the rod up. This raises the center of
gravity, and the upper end of the rod falls,
turning the axle and immersing the other pair
of cords. Evaporation relaxes the top cords, 80
that the rod is again pushed UP. Slow rotation
can be thus kept up. and with several rods and
sets of cords. it can be made fairly regular and
continuous.
Late cancer research has shown that the dis
ease exists among all races of men, as well as in
domestic and wild animals, and that liability to
it is greatest in the last third of the life span.
ASs
The art of the dyer is one of great Importance
in Persia and the secrets of special colors are
carefully guarded in certain families, and have
been handed down from father to son for many
generations. warning to would-be buyers OF
high grade oriental rugs has been given by U.
s. Consul W. F. Doty, of Tabriz. A proper
guaranty that only vegetable dyes and fxatives
have been used should be secured, for unknown
vendors are almost certain to sell rugs colored
with chemical dyes, all of which-though there
are different qualities-are liable to change on
the first exposure to bright sunlight Since
their first introduction, about 1850, the use of
coal tar preparations has been increasing, the
cost being only one-third or one-half as much
as that of the vegetable dyes. The cultivation
of the madden plant. which yields more than
sixty of the finest shades of red and yellow, has
greatly declined in Persia, and the demand for
the root is now small. Between thirty and forty
shades of yellow are given by the shell of the
pomegranate. Perhaps fifty varieties of blue
are given by indigo; and for the best blacks and
other coloring material it is said that there are
employed hundreds of herbs and varieties of
bark, vegetable and even some animal matter.
Iron filings are used for cheap and fugitive
black.
The treating of skin diseases by powerful light
rays is rapidly becoming popular in Europe,
and elaborate equipments, costing up to $780,
600, are being provided. A motor-car fitted
with x-ray apparatus is to make regular tours
over a large district in Belgium. A London
expert has distributed fifty x-ray machines in
English hospitals and institutions, and leading
physicians find it desirable to give attention
to light healing. Besides the x-rays and the
electric light baths there is the ''infra-red"
light, which, producing intense heat, is used to
draw the blood to some particular part of the
body.
The perpetual lamp" of Prof. Molisch is a
glass flask of gelatine supporting a colony of
phosphorescent bacteria The light is less than
that of candle, but is sufficient for photogra-
ply, and terminating peas and lentils turn to it
as a source of energy. Being without heat rays
it represents the much sought cold light.
srs
Nickel having come into extensive use in the
kitchen it is important to know what action
food substances have on it. and how its COM
pounds may effect a person eating food con-
tanning them. Late Russian experiments are
reassuring on both points. Substances boiled
in nickel vessels took up q small amount of the
metal-from 0.O02 with some foods to as much as
| per cent. when the acid present is excessive;
but solution containing per cent. of citric
acid and per cent. of common salt had only
OLA per cent. of nickel after boiling hours in
nickel vessel and then standing II hours in the
same vessel. The physiological effects of nickel
salts were slight, while there was no tendency
to accumulate in the body after repeated doses.
Nickel in quantities up to a quarter of gram
daily in the form of lactate or butyrate, was
given to two dogs for 202 days with no result.
and dog that died after taking 81 grams about
third of an ounce) In 40 days had no nickel in
its body, its death having been due to some
other cause. Doses as large as to grams daily
were necessary to give any symptoms of
poisoning.
The leather substitute of Jules-Prosper
Gauthier, French chemist, is combination of
rubber, with vegetable animal or mineral fbers,
and is claimed to give material of high quality
and low price. With 80 per cent. of ibers and 20
per cent, of pure or mixed rubber good results
are obtained, the proportions being varied to
give different pliancy and tenacity. The abers
may be spread out in bands and glued together
with melted rubber, or they may be impregna-
ted with rubber and compressed in molds or
consolidated under rolls. If desired, the pro-
duct can be vulcanized.
-.
Instead of being obsolete and simply an in
teresting relic, the hour-qlass in various forms
is a twentieth century necessity. machinist
authority points out that for such purposes as
timing, hardening and tempering heats in twist
drill manufacture, where seconds or minutes
must be gagged accurately, nothing serves like
the hour-glass with the right amount of sand.
Accuracy to fractions of second can be had
much more easily than by watching the hands
of watch
When Baby was SICK we gave her Castoria