SOUTHERN CGALTFORNIA ACADEMY OF SCIENCES . 2 
being specially adapted to long exposures of faint objects, while the 
latter served best in the observation of bright objects. 
The stereopticon was then brought into use, and the glories of the 
heavens revealed in a way to entrance the soul and to overwhelm one 
with the realization of the infinite magnitude of God’s creation. Suns, 
planets, satellites, starclusters, and nebulae, in all the grandeur of their 
brilianey and infinitude, were thrown upon the screen and Iucidly ex- 
plained to the extreme delight and fascination of the audience. 
Very many of the pictures were the result of Prof. Ritchey’s own 
observation and development, and they rank among the best that can 
be found in the world. A vote of thanks was extended to the speaker 
for his instructive and uplifting address, and the meeting adjourned. 
MELVILLE DOZIER, Secretary. 
March 4th, 1907. 
For the lack of a quorum present, no Directors’ meeting was held 
this evening. In the absence of the President, The Secretary introduced 
the speaker of the evening, Dr. Holdridge O. Collins, who discussed the 
subject, ‘‘The Planet of Jupiter,’’? in all of its phrases. The speaker 
said in part: ‘‘Of the eight planets circling our Sun, the great moni- 
tor is Jupiter. Great by reason of his immense bulk, his intense bril- 
lianey, and above all by reason of the influence he has upon human life 
on our globe in furnishing the first certain means of measuring the ve- 
locity of light, and the longitude on exact location of places relative to 
each other. 
His density is only one fourth that of the earth; and, were all the 
known planets assembled in one body, their combined mass would be only 
two-thirds of that Jupiter. His rotation is accomplished in about 9 hours 
and 56 minutes, while his revolution about the sun consumes 11 years 
and 314. 92 days of our time. 
Jupiter being inclined but a little more than three degrees to the plan 
of his ecliptic, the variation of seasons and in the length of day and 
night is exceedingly small; but as the mean density of Jupiter is nearly 
the same as that of the Sun, it seems not unnatural to suppose that the 
planet is intensely seated, and that this inherent heat is what produces 
great changes in its atmosphere. Another reason for believing Jupiter 
to be incandescent is that the light secured from him is far in excess of 
what he would reflict if his surface was hke that of the Moon. 
Jupiter therefore, cannot be the scene of animal or vegetable life. 
The conclusion may not be true of the four chief sattelites of Jupiter, 
whose conditions may reasonably be compared to those of the four 
planets nearest to the Sun. 
The late discoveries in the solar sy stem have excited intense interest, 
and with the increase of power in new reflectors and refractors, this gen- 
eration may come to some accepted conclusion as to the existence of life 
upon other worlds of our system. 
The speaker went with minuteness into descriptions of Hros and 
orbital peculiarities, and of the body ::T. G.’’ in its remarkable relations 
to the planet Jupiter, the entire lecture being replete with important 
facts and suggestive theories. 
At the close of the lecture a brief discussion ensued. The Secretary 
read a statement from Chief Justice Melville W. Fuller, Chancellor of 
the Smithsonian Institution, announcing the appointment of Charles Doo- 
little Waleott, L. L. D. as Secretary of the Institution, to succeed the 
late Camuel Pierpont Langley. 
The Secretary also read a communication from the International Zoo- 
logical Association, writing the Academy to participate in the Seventh 
