The morning star and Catholic messenger. [volume] (New Orleans [La.]) 1868-1881, 1868-08-16
SCIENTIFIC AND MECHANICAL.


being separated is ground into IN impal-
pable powder, and then again mixed with
the flour. In this way all the nutritious
ingredients are preserved, while the fneness
OF the flour is not affected.
MANUFACTURED MILK.-Mr. j. G. Morton
has published good article on "TOwn-
ik"-that is, the milk sold in towns
from which it appears that the customers
suffer in health and in pocket from the
roguery which prevails among the retailers
Ten samples of milk were bought at shops
in Blackfriars, the Strand, ST.. Giles's, and
north and south of Hyde Park. Only one
was pure in all the others, there was more
water and less cream, and the price was
from fourpcnce to fivepence quart. A cal
culation was made, that by selling milk at
tivepence, after adding one-ffth to the
water, and taking away one-third OF the
cream, the yearly profit on sale OF one
hundred gallons II day would be two thou
sand pounds. So dishonesty makes money,
while infants die for want of good milk,
aud the population ut large is dcfraudcd i'll
one of it's prime articles of nutrition.
LIoUIFYING LAUGHING GAs.-Thc uni
form efficiency and safety of laughing gas
as an anesthetic has prompted the British
Medical journal to suggest that bottle be
made strong enough to hold the gas in n Ii
quid form, and of such weight and dimen-
sons that it may be easily carried by the
surgeon in his daily rounds. At present it
is used by dentists from large gas-bags, into
which it is placed as soon as made. Laugh
ing gas is composed, according to the new
notation, of two atoms of nitrogen AMI one OF
Oxygen. These elements are the rrincil, con-
stituents OF common air. Laughing gas or
nitrous oxy.ie can be li4uilied under pres
sure of seven hundred aud fifty pounds per
square inch when at the temperature of for
ty-tivc degrees Fahrenheit. The most con
vcn;cnt and safe receptacle for the liquid
would be a brass or copper tube, not more
than Il foot in length, and of such thickness
as to resist pressure of at least fifteen hum
drcd pounds, or several small tubes of the
ordinary thickness might be united side Ly
side and made entirely safe.
TIE ClIL>NYDEH.-Mr Poucllct, Director
of the Roucn Museum of Natural History,
i'm his new work thus describes the habits
of this curious bird: ''The specklcd chla
myder is Il bird resembling our partridge,
bit is distinguished by its deep color, re-
lievcd by clear spots, and by its neck,
which is adorned will, a red collar. For
the location of their nest the couple choose
an opea spot exposed to the sun. Their
first care is to make path of round pebbles;
when they deem it sufficiently thick, they
plant in it a little avenue of branches. They
arc seen, fer this purpose, to bring from the
country slender shoots of trees of about the
same size, which they thrust solid!y by the
thick end into the interstices of the stones.
The branches are disposed i'll two parallel
ROWS, converging Il little i'll snch manner
that they form miniature shrubbcry. The
plantation is u yard III lensth, and is s7tti-
cicutly wide to allow the two birds to walk
alongside of each other in the interior This
grove being finished, they devote them
selves to embellishing: Each starts out for
aging in the fields, and brings back all the
shells, birds feathers, all that can charm
the eye. These trophies arc suspended at
the entrance to the grove, which soon be-
gins to shine i'll the sun like Il palace of the
Arabian Nights. In the places frequented
by the chlamyders, if Il traveller loses his
watch, his knife, his seal, he does not spend
his time looking for it on the ground-he
knows where to find it.'
PROPAGATION OF SOUNDS IN TUBEs.--M.
Kundt has made a series of elaborate ex-
periuents to detelm: n, the velocity Of
sounds in tubes. He finds that the velocity
diminishes with the diameter of the tube,
but this diminutiOn only becomes sensible
the length of the air-waves producing n
given sound. Starting with this diameter,
he finds the velocity of sound diminishes
with the increase of pitch, or in other
words, the velocity increases as the length
of the air waves increase. In tubes OF small
diameter lie discovered that fine powder
distributed over the interior checked the
progress of sound in direct proportion to
the quantity and lightness of the powder;
yet rOughness in the tube itself does not
retard sound. The amplitude of the air
waves or the intensity of sound was found
to produce no influence on the rate of pro-
pagation. In this connection We may aiinde
to the experiments recently made by NJ.
Regnault, OF the French Institute. He used
the new sewers of the city of Paris for the
purpose of determining the force of the air
waves producing sound. BY firing pistol
in tubes and sewers of various diameters he
found that the sound was carried, in pas
sage az inches in diameter, through dis
lance of one thousand two hundred and
eighty-two yards; in a passage lis inches
in diameter, four thousand one hundred and
ninety four yards in q passage forty three
inches in diameter, ten thousand four hun
dred and ninety four yards. The IN inner of
constructing the tube and the material of
which it il composed exercises great in