The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1890-12-27
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
MIMICRY,

MIMICRY.
The great principle of mimicry, according to
the address of Mr.. E. B. Paulton to the British
Association for the Advancement of Science,
was first enunciated by Bates in 1862, and has
since been confirmed and extended by numer-
Gus observers. The colors of animals are now
known to have three important uses-conceal-
ment, signalling or warning, and mimlcry.
Examples of color for defensive concealment
are found in green fish, which would be con-
Spicuous away from its constant home among
the leaves fthe Zostera, and in brown moth
which always lives among brown leaves; while
concealment as a means of securing prey may
be seen in Brazilian frog, which lies partially
buried in the ground which it resembles.
Warning to enemies against something I'M
pleasant is given by the conspicuous appear
ance of certain unpalatable moths, and the
white tail of the rabbit is a signal to its friends
in time of danger. Mimicry might be defined
as false warning and signalling colors, repelllng
enemies by the deceptive suggestion of some
thing unpleasant and dangerous, or attracting
prey by the deceptive appearance of something
pleasing to them. Protective mimicry is illus
trated by Indian and African butterflies, which
closely resemble other species possessing nau-
seous taste and conspicuous appearance. In
stances of aggressive mimicry are found In GER
tain flies, which lay their eggs in the nests OF
bees ETC.. and are colored like the latter, so that
they can approach with impunity. Allurlng
coloring may be considered under this head,
and illustrated by a lizard with pink flower
like structures at the corners OF its mouth, to
attract insects by a freSh-water turtle, which
attracts its prey by dangling two worm-like
filaments and by the lures of various fishes,
which fishes, which are phosphorescent in the
case of deep-sea forms. An interesting fact is
that even the foreign objects commonly asso-
ciated with mimicked species may be copied,
an example being a South American insect
which resembles a common leaf-carrying ant
together with the leaf ITSELF
NOVEL TREATMENT OF DIPHTHERH.
In treating case of-grave diphtheria in his
own son, DIR. Babchinski, European physl-
cian was surprised to note a rapid change for
the better Immediately after the appearance of
erysipelas on the face. The fever abated, the
false membrane disappeared, and the cure was
speedy. A similar coincidence was observed
in other cases, and suggested the idea of inocu-
lating victims of diphtheria with blood from
patients suffering from erysipelas Theexperi-
ment proved very successful in several cases.
Cultures of the erysipelas microbe were then
used for the inoculations and were equally eff
fective in causing the symptoms OF diphtheria
all cases too mild to give uneasiness. DIR: Bah
chinski concludes that this treatment should
rob diphtheria of its dangers.
A SENSITIVE BALANCE.
In lecture to the British Association on his
now celebrated quartz fbres, Prof c. V. Boys
,ibited the application of the minute threads
'spenders for extremely delicate apparatus.
eat from candle at the extreme end OF
u was sufficient to turn a mirror sus-
rom one of the fibreS, the movement
Lade visible by the spot of light reflected
Green. A musical note ever produced
ttion the spot. What was perhaps even
re wonderful was the demonstration that at
raction so small as the 25-millionth of grain
might be weighed, the attraction of gravity of
that amount producing visible effect on tor
sion balance made of the quartz fibre.
SCIENCE AND CURIOSITY.
81 can trace for you the scientific uses of curl
osity" declares DIR. Andrew Wilson, Just as
Tyndall sought out for us many years ago the
scientific uses of the imagination. What is all
science, may 1 ask, save curiosity-arranged,
orderly, systematic curiosity To question the
why's and 'hows of nature is the business of
the scientist. Hequestions and oss-examines
nature lust as barrister badgers his witnesses;
and, as result our scientific friend gets at the
truth about things by reason simply CT his Gu
riosity. He has no need to be curious, but his
desire to know is born in him. 1t is part and
parcel of his constitution, and in the exercise of
it he builds up the knowledge which makes
him and his race, Intellectually, physically
nay, even financially,-rich. This is the science
of curiosity; but for curiosity there would
have been no science at all. HencefOrth you
must think of curiosity, bridled and trained, as
the kind of genius which takes us all as chill
dren by the hand and leads us, eager to know,
that we may learn the secrets of the universe "
BUT WHAT IS ELECTRIC ENERGY?
The idea that electricity flows through a wire
somewhat as water flows through a pipe is
likely to pass away, as reasons appear for be-
lieving that the energy is not transmitted by
the wire at all, but by the surrounding ether.
In some experiments by Prof. ]. J. Thomson,
the velocity of electric disturbances along a
wire surrounded by air was nearly double the
velocity along the same wire surrounded by
sulphur, and the velocity of the discharge
through a vacuum tube 20 feet long was COM
parable with that of light. The conclusion is
that the conductor merely guides the discharge
impelled through the ether.
MISCELLANEOUS
Prof. w. H. Preece has found great differ
ence in the magnetism that can be impaired to
different makes of steel, eleven specimens vary
ing in their mean induction from a power of
1856 to 2,540.
In a criminal lately beheaded in France, the
beats of the heart were noted during more than
six minutes, and experiments were made to
demonstrate the independence of the ventricu-
lar and auricular contractions This is said to
have been the first time such observations were
ever made on man.
Mont Blanc now has, at IA 800 feet above the
sea- the highest meteorological observatory in
the world. The Sonnenblick station is 10, 10
feet above the sea, and the Pixies Peak station
IA, 1874 feet. The registering instruments of the
new station require attention only once in Is
days.
Atthe French Association meeting. NJ. CODES.
of Buenos Ayres, contended that Sll living ami
mails have surface of absorption and respira-
ton; and that oxygen introduced by hypoder
mic injection is absorbed by the capillaries in
the same way as when inspired by the lungs.
The hypodermic respiration thus set up is sug-
gested as likely to be useful in lung disease.