St. Paul daily globe. [volume] (Saint Paul, Minn.) 1884-1896, 1884-09-07
SCIENTIFIC MISCELLANY.

made some interesting investigations on
color-blinpness with an apparatus in which
two spectra are oyerlapped so as to produce
various mixtures of colors, which are ex-
amined and described by the person under
test One Of the things he has shown is that
the majority of people require only half as
much red in the mixed spectra to turn yellow
into green as he does himself By far the
most common form of color-blindness ia
blindness to red. DR. Guthrie, who is so
afflicted. is more than usually sensitive to
blue light; and others have been found with
an abnormally acute perception of red One
person appeared who suffered from the very
rare defect of being color-blind to green.
These results have led an English astrono
mer to suggest that some of the startling
changes of color alleged to have been noticed
among the heavenly bodies have really never
taken place, the supposition of such changes
having probably arisen from the different
-perceiying power of different observers.
The temperatures at which the common
gases become liquefed are given as follows
by Prof: Dewar, the numbers expressing de-
grees below zero Fahrenheit: Carbonic acid,
III; nitrous oxide, 1870; ethylene, the chief
Illuminating constituent of common coal
gas, 154119; oxygen, 299; nitrogen, 800; air,
314; carbonic oxide, 3151%. The greatest
cold yet produced by man-32S degrees be-
low zero was obtained by two Russian physi-
cists by the use of liquid oxygen.
An establishment in the Hebrides which
treats sea-weed for its iodine, according to
Mr.. Edward Stanford, f. c. S., obtains an
Illuminating gas as bye product. The pro-
cess also yields q very light and porous char
coal, ammonia and tar
CHINESE ALCHEMY.-An eastern writer
declares that there is now no reasonable
doubt that the old Arabian alchemists and
others derived their ideas on the transmuta-
ton OF metals into gold and the belief in
immunity from death by the use of the phil
osopher's stone from China Mercury is sta
ted to have been the philosophers stone of
which Geber and others wrote, and cinnabar,
redsulphuret OF mercury, was known to the
Chinese as early as the seventh century be-
fore the christian era, its occurrence on the
earth's surface being said to indicate gold
beneath. Mercury was excessively employed
by the Chinese as medicine, and in the
ninth century an emperor was killed by an
overdose. Their medical books say takes 200
years to produce cinnabar; in 300 years it
becomes lead; in 200 years more it becomes
silver; and then by obtaining a tran Storm
ing substance called 'vapor of harmony it
becomes gold. This doctrine of the transfer
nation of mercury into other metals is 1000
years old in China. The Chinese contend
that when mercury is taken into the animal
system it not only prolongs life but expels
bad vapors, poison, and the gloom of an un-
easy mind.
Some remarkable photographs of a pistol
bullet in its flight-under The illumination of
an electric spark-have been secured by
Prof E. Mach of Prague. He has also pho
graphed the air streams which one may see
over a Bunsen burner placed in sunshine:
and has even obtained pictures of waves of
sound, these last being made visible by a
method in which advantage is taken of the
irregular refraction of light by the air set in
vibration by sound.
A simple sunshine recorder is made by
Prof. H. Macleod By placing globular bot.
tie of water before camera in such posi-
ton that the focused ray falls on Il sheet o.
sensitized paper in the camera box. AS the
sun makes its daily journey it produces
curved white line on the paper, and when
clouds cross the sun the line stops
THE CHOLERA GERM.-That the cause of
cholera is a miscropic orga nism was first rec
ognaized in 1864 by Hippo Pacini, of Flor
enc e,the pa rasite being in 1882 classified by
Tommasl-Creduli among the schizomvcet or
germs which multiply by simple division
Pacini supposed that the organism attacked
the mucous membrane OF the intestines, but
his doctrine was riduculed or disregarded
until the same conclusion was reached by the
commission of of eminent German patholo.
ogist which has Just investigated the subject
in Egypt. The cholera germ multiplies in
the soil where the eXcretions of cholera pa
tients have found their way; but it may also
ind in nj in had oh
been fouled by such eXcretions and washed
without disinfectants, as was shown in 1856,
when poor Tuscan woman died with chol-
era received from linen which had been in
fected an entire year before. Tommasi-Cre-
dull remarks that cholera in Europe is al
ways an importation from the cast, never
becoming acclimatized like small pox, and
that it becomes epidemic only when the ex-
cretions containing the germ find a soil IA
vorable to its multiplication.
Japans meteorological system now COM
prises twenty-three observations in the most
important places throughout the country.
From each district three weather reports
daily are sent to the central observatory at
Toxic where they are prepared for publication
by the leading journals of the seaports.
An investigation of the saltpetre beds near
Cochabamba, Bolivia, leads Mons. SAGE to
conclude that this vast deposit, large enough
to supply the whole world with its nitrate of
potash is the result of the de composition OF
an immense collection of fossil animal
remains.
French chemist has found, under GER
tain conditions an observation of the electric
resistance of water seems to supply delicate
test of its purity,