Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1880-07-14
POPULAR SCIENCE.

4 VI " LIAM RO4A1tOAs
The Duke of Argyll, writing to the Ma
tire, gives, as he believes, the only case
among the feathered tribes in which vocal
is replaced by instrumental music. The
peculiar sound made with the bill of the
woodpecker upon trees apparently serves
the same purpose as the song OF other
birds, and ends when the eggs are Matched.
The Duke had lately an opportunity OF
closely observing how the lesser-spotted
woodpecker, or picus minor, behaved at
pairing time, and the results of his o5serva-
tions excite curiosity. He is quite certain
that the sound made by the bird has moth
ing to do with the quest for food. 6 The
bird selects one particular spot upon the
trunk or bough of tree, which spot is
naturally sonorous from the wood being
more or less followed by decay. The bird
returns to this precise spot continually
during the day, and produces the sound
by striking on the spot with its bill, the
stroke being repeated with rapidity
which is really incomprehensible, for
it quite eludes the eye. 1t is effected by
a Migratory motion of the head, but the
vibrations are so quick that the action
locks like single stroke. After short
pauses this stroke is again and again re.
newed, sometimes for several minutes to-
gether. During each interval the wood
pecker looks round it and below it with
evident delight, and with an apparent
challenge of admiration. The beautiful
crimson crest is more or less erected The
whole performance evidently takes the
place OF song in other birds. The nest is
not in the same tree as the one struck by
the bill of the male. Similar sonorous spots
in the trees in the neighborhood are Sc
lected if available, SO that the observer
concludes that the hen bird as she sits on
the nest is serenaded from different direc.
tions, and with such variety in the sound
as the change of tree may produce.
Lord Rayleigh has described plan for
demonstrating that yellow color can be
formed by combining red and blue. He
mixes a red solution OF chromate of potash
with blue solution of litmus, and, on fill.
ing it into a glass cell of certain thick
ness, the light transmitted through it
seems to be yellow. Plates of glass coated
with gelatine impregnated with chromate
of potash, placed side by side with plates
coated with gelatine lmpregnated with lit
mus, also transmit yellow light Lord Ray
leigh finds, however, that the eyes of diff
ferent persons vary considerably in their
power of approaching the tinge of the
transmitted yellow; but this class has
nothing to do with blindness, since
all the persons tested could distinguish at
once the components with Accuracy.
The Lancet says it would be difficult to
point to more probable source of infec-
ton in the search for causes of disease in
private families than the houses where the
practical work of dress-making is per-
formed. 1t recommends, therefore, the
erection of public work rooms, we'll
arranged and under proper supervision, to
which the poor might bring their work and
finish it In cleanliness, comfort and peace,
The suggestion appears to be quite feasible.
and If it is carried out it will certainly i'm
prove the general health of cities and cor
rect other crying evils. 1t is as well worth
the attention of the political economist as
that of the pbilanthropist
AT meeting of the Royal Society, Lon
don, held on May 9th, Mr. Preece de-
scrihed very simple form of telephone in
reading a paper on some thermal effects of
electric currents. Very thin wires acquire
and lose heat so rapidly, and are SO sens;-
tive to linear expansion, that, if inserted
in the circuit of inicrophone transmitter,
they produce sonoFous vibrations A mere
sounding hoard or disk and fine wire are
all that need be used to reproduce speech
with the same faithfulness that Bell obtains
with electro magnetism, Edison with cleo
tro-chemieal agency. and Hughes with his
microphone principle.
~ Lepinay has drawn up his report re-
ga ding the canal to connect the Bay of
Biscay with the Mediterranean. He pro-
poses that the canal start from Bordeaux,
and, after traversing 252 miles, terminate
at Narbonne. The number of locks would
be 81, and long enough to admit vessels of
-439 feet in length. The depth would be
q feet 9 inches, and the breadth at the
surface where the canal is to be of single
width lS4 feet, and where it is to be of
"double width 262 feet. The estimated
cost is $ll0,000,000 By means of this
canal ships using steam can go from sea to
sea in 81 hours.
Potato flour, or the dried pulp of the po-
tato, is attaining great Importance to the
arts. 1t is stated that in Lancashire, Eng
twenty thousand tons of it are sold an
nually, and it brings at present in Liver
pool about double as much in the market
as wheat flour. 1t is used for sizing and
other manufacturing purposes, and when
precipltated with acid is turned into
starch. When calcined it is employed as a
dressing for silk.
An improvement in the process of
bleaching vegetable fibers has been made
by Bayle and Pongtigsia. They add mar.
r4o r,ln = 10
OF fax, or Panama bark, to basic bath of
alkali or chloride of lime, with, as they
claim, the effect of limiting the destructive
action of the chloride, and of promoting
the solution of the gummy and .resinous
matters that adhere to the raw fiber.
A writer in the Journal Of Science fully
supports DR.. G. NJ Boards assertion that
ono climate, no institutions, no environ
ment can make insanity common except
when united with and reinforced by brain
work and indoor life, carried on under
the influence of anxiety.
4 mineral carbon has been discovered at
Lake Orega. 1t is not easily burned, and
ii the forms of coal be arranged in a
series-lignite, bituminous coal and an
thracite 1T may be placed after anthracite,
as IL Is GILL iilOIc uINSSlSll VI OiSdiC CHAR
acter.
Smallpox is increasing so rapidly in Paris
that it is proposed to make vaccination.
compulsory While S5S persons died of
this disease in that city last year, not less
than l,O3s died of it in the first four
months of the present year.
T. A. Brecklebark estimates that in a
single decade 100000 persons engaged in
industrial pursuits in Great Britain sustain
personal injury or are killed; in mines,
300, GOO; in railways, 10000, and in fac
tories, $50 600.
There can be no longer any doubt that
the alligator does exist in the Old World,
as two fine specimens taken from the
Yang se-kiang are now.in the Berlin 10
illogical Museum.
The constructors of the railway up
Mount Nesuvius have adopted the Ameri-
can double iron-rope system as the best
means OF raising and lowering the trains.
The climate of North Africa might,
thinks Dr. Theobald Fischer, be more
easily improved by the planting of forests