Mineral Point tribune. (Mineral Point, Wis.) 1869-1938, 1872-02-29
Scientific Notes.

/ ''l'VAtiAlS. lut pTOltCtlOn is III the
color of the paper, which cannot be
chemically analysed, neither initiated
by photography. Each state can have
Its own color, which can be kept Sc
cret. The process is not more ex-
penslve than that employed in prepar.
ing the present paper.
AT recent meeting of the French
Academy of Sciences, Recquerel ex-
pressed the opinion that the aurora
does produce sound and in confirma-
uon OF this view cites the observations
OF faul ROLLER, nrouaut, who started
from Paris in December last, and de-
scended fourteen hours afterwards in
Norway, on mountain mt an elevation
of ZOO feet; Il saw, through a thin
fog, the moving Of the brilliant roys
OF an aurora borealis, spreading all
around It's strange light Soon after
ward an incomprehensible and loud
roaring was heard, which, when it
ceased completely, was followed by a
strong smell of sulphur, almost suno-
eating. Prof LOOMS and other meta-
biologists have obtained no satisfactory
evidence that the aurora ever emits
any audible sound. They believe that
the noises ascribed to the aurora are
! due to other causes-such as the wind.
or To that low temperature of snow and
Ice which sometimes produces sudden
movements i'll masses.
MIR. j. A. HUI, in the November
number of the franklin Institute ,Jour-
nal, proposes a new form of rejecting
telescope. The mirror will be firmly
imbedded in rock or wall, and facing
1t will be placed a plane mirror with n
central opening moving about horizon
tai and vertical axes. The light from
celestial body is reflected from the
plane mirror on to the curved and
stationary one, whence it is reflected
back through the central aperture of
the stationary mirror and forms n focal
image behindit, which is then examined
IN the usual manner with an eve piece.
The advantages claimed for this ar
rangement are that the curved mirror
can be made of larger size than hereto
fore, because 1t is stationary and will
not be deformed by being placed
IN different positions, as is now the
case; also, no heavy and expensive
machinery will be required to
move the mirror, for the plane mirror
alone can bring into view every part of
the heavens, and will only require sim
pie and light machinery to do this. We
are forced to with hold our entire ap-
proval of this ingenious scheme for the
good and well-establisbed reason
known to all practical opticlans) that
We have never yet had the good fortune
to see surface of speculum metal or of
glass which was plane enough for the
purpose proposed by the inventor.
Any departures from truly plane sur
face will be greatly magnifed by the dis
stance through which the light is sent
by two reflections. Indeed the most
difficult problem In art il la produce
..,-iy pl,tnc surface.
DIR. p. MULLER has given, in the
Moniteur Scienttiuue, an account of
his researches, and his conclusions are
as follows Meat extracts are neither
nor indirectly food for they
do not contain albumenoid matter.
neither do the heterogeneous principles
which they contain arrest dis-nssimila-
ton; that is, they do not prevent the
waste of the organic matter which
composes the body. In small doses,
these extracts are useful, by the stimu-
liant action of the POTASH salts, which
promote digestion and circulation: in
strong doses, too large at once, these
substances may have "A very injurious
effect When given to convalescents
from serious diseases, especially if the
system is exhausted by prolonged alb
the potassa salts pre-
sent In these extracts in large
quantities, viii act more iniuri-
ously, because the system has lost
great deal of chloride Of sodium; in
stead, then, OF promoting digestion,
these substances will interfere with it,
~, by the direct action of the salt of
potash on the blood globules, whereby
The absorption of the oxygen by these
ylobules is greatly decreased GU, by
jhe predominance of such salts in the
serum of the blood which only phys.
cally dissolve carbonic acid, and do not
allow the normal quantity of that
yas to be exhaled, and thus impede the
access Of oxygen. Medical men should
pear IN mind that if given alone, these
extracts, and likewise beef tea, are no i.
1utriment, and only tend to keep the
weak, being thus i'll fed,
)r rather, not fed at all. These conclu-
;ions are substantially those entertained
by Liebig and many other investigators
n the same fold
Con SCOTT, Of South Kensington
England, has invented q mortar for
which several advantages are claimed.
It is made by simply mixing with the
water small quantity of sulphate of
line in the form of either natural gyp-
sum or plaster of Paris burnt GYPSUM.
Instead of sulphate of lime proto-sul-