The sun. [volume] (New York [N.Y.]) 1833-1916, 1906-11-28

ITOm US L0Au J0OHG Oh b10 olAJu uIdROltud0
This must be very seriously examined
in every possible way. One conclusion OF
Prof. Comstock's that will be readily 40
cepted is that there are about a thousand
stars, or, say, as many as can be instantly
recognized by the naked eye in any one
half OF the sphere, which 90 along with
the solar system in its motion through
space. He seemed to speak as II this were
a pretty sharply definite group or cluster.
h whole paper was most excellent and
was admirably presented.
DR.. George E. Hale, director of the Car
negie Institutions solar observatory on
Mount Wilson and parhaps the most brill
liant astronomical investigator now active
among a number who command our ad-
miration, gave a paper on sun spot spectra
and their bearing on stellar evolution.
With his always rapid delivery, accelerated
by his evident anxiety not to encroach
upon the time Of those who were to follow
him, he touched upon a great number OF
points; but il there was any that has not
been set forth in the swift succession of
recent publications OF his wonderfully
active observatory 1t escaped the reporters
slower moving attention. That tho spectra
Of many stars show peculiarities of tho
relative intensities Of different lines OF the
same metal, which peouliarities are strongly
marked in the sun spots and are in all
probability due to cooling or to lower tenn
perature, has recently been shown very
clearly by Dr.. Hale; and perhaps il will
be possible soon to distinguish with GER
tainty between a comparatively cool star
which has not yet become hot and one whose
heat is becoming exhausted. Sir Norman
Lockyer attempted to make this distinction
in his book on inorganic evolution, but
with very doubtful success. At present
the prospect is more hopeful. DIR. Hale
mentioned a part Of his observatory which
embodies a most vital condition Of sue
eessful research. This is a chamber in which,
upon an annular pier. are kept, mounted
and ready for instant activity, a variety
Of instruments for examining terrestrial
spectra of all kinds under all sorts Of con-
ditions of pressure, temperature, mag
netism, &c. Thus when any phenomenon
is observed astronomically and the sug-
gestion arises that it might be due to GER
tain conditions the observer can without
delay walk into this chamber and make
the observation which shall either con-
firm the suggestion and allow further re-
search to proceed with confidence or shall
negative it and show that a different n.y.
pothesis is required; or perhaps shall partly
confirm it and partly refute il, showing
him that he is in the way of the truth but
must modify his theory. Rapidity is a
more vital factor Of success in that mingled
process OF observation and refexion that
constitutes research than scientific men
nave usually seen hat it H.. The closer the
union Of the ~observational part and the
reasoning part the surer will be the aim,
other things being equal; and DR.. Hale,
who is a prompt snatcher at times fore
lock, has here set an example which will
bear good fruit.
DR.. Alexander Graham Bell next read an
extended paper upon flying machines.
He began with a historical introduction in
which he reafflrmed, as an y witness,
the facts OF Prof. Langley's experiment
of 1899 upon an aerodrome having a wing
spread of IA feet and propelled by steam.
mo one," he said, who had witnessed the
extraordinary spectacle of a steam engine
flying with wings in the air, like a great
soaring bird, could have doubted for a
moment the practicability Of aerial flight
He maintained that the later disaster
proved nothing. He then described the
machine Of the Wright brothers. They
have kept in the air for 80 minutes, and
have described figures of eight. The
weight carried was nearly two pounds to the
square foot Of supporting plane. Their
velocity has been about t~hirty-seven miles
an hour. DR.. Bell thinks, however, that
such high speed is dangerous, at any rate in
theinfancy Of the art, although IL is necessary
II the weight Is to be so great in proportion
A. ~ z-@1-. -l.-- IL -1-A kA-.I
exactly why planes that are nearly horizon
tai are necessarily deficient in stability.
For that reason he prefers a structure built
up of tetrshedral cells. He described a
kite made and flown by him. Each cell
consists OF two horizontal rods each about
10 inches long, m running, say north and
south, and the other east and west, each end
of each being connected by means OF a
rod of equal length with each end of the
other. The two lower t~riangles so formed
are covered with silk. His kite was built
up as follows: The lowest layer consisted
of IL rows Of 10 OF such cells in each row;
the next layer Of II rows of Ia cells in each
row, &c. Each layer had one fewer rows
than the layer below it and one more cell
in zach row. Thus the twelfth layer con-
sisted OF a single row of "a cells. There
were 800 cells in all. These cells weighed
about 40 pounds, and some Strengthening
material brought the weight up to 81 pounds.
In a breeze not sufficient to raise white
caps on the surface of the sea-, this kite
carried up, besides its own weight, 90
pounds of manila rope and a man whose
weight was 1856 pounds, making 2ss pounds
in all. This was about one-third the weight
to the square foot Of supporting plane that
the Wright machine carries, but the tetra-
hedral structure is far more stable than
Wright's at the same velocity.
Thursdays meeting was opened by
Prof. Arthur Q. w ebster Of Clark
University, W orcester, Mass, who de-
scribed an apparatus for the accurate
measurement Of the intensity of sound.
Prof. Webster seems to have constructed
the apparatus long ago, but to lave brought
it forward only when there appeared To
be a real demand for such a thing. There
is a pressure gauge consisting Of a hin
disk Of glass which responds p~erceptibly
to a difference of pressure of one hundred
milionth of an atmosphere, which is the