Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-02-03
SOLAR LIGHT AND HEAT.
Prof. Searle's Startling Figures Regard
ing the Radiant Energy of the sun.


Prof. George NJ. Searle continued at the
Catholic university last Friday his Friday after
noon astronomical course by explaining the
various methods used in the computation of
the amount of light and heat radiated from
the suns surface. He showed how, by means
of a beam Of sunlight passed through lens,
the direct light received from the sun has been
determined to be 1000 times as bright as the
light of a candle yard distant. He narrated
Prof. Langley's experiment in measuring
the comparative brightness of the sun and the
most highly heated molten steel at one of
the great Pittsburg foundries. 1t was found
that eighty-seyen times as much heat and 5000
times much light is radiated from n square
foot OF the suns surface from that of the
metal After showing the use of the burning
glass IN determining solar heat and describing
the Poulllet pyrheliometer, the lecturer went
on to give number OF interesting figures re-
garding the amount of energy represented by
the radiated heat of the sun. Stating that a
horse power consisted in force sufficient to
raise $500 pounds one foot in one minute, he
showed that the amount Of heat radiated from
the sun to the earth Is equivalent TO 304 trill-
ion horse power, and the total amount radiated
from the sun into space is 600 sextillion horse
power, or 10000 horse power for each square
foot of the suns surface.
He described the Mouchot and the Cresson
solar engines for the utilization of the heat of
the sun in mechanical processes. which have
both been successfully operated, the first
named at the Paris exposition and the second
in New York.
After the close Of the lecture the rector.
Bishop Keane, made the announcements for
the public courses OF February.
Prof. Searle's course will be continued every
Friday In February ut 4:45 O'Clock, all the
lectures being illustrated, Us usual, with stere-
oscopic views.
The Wednesday lectures will be by Bishop
keane himself and will be devoted to a review
of Herbert Spencer's First Principles" The
bishop recommended, preparation for the
lectures of this course on the part of those who
expect to attend, reading OF the first few
chapters Of Mr.. Spencers book, which will
each be the subject Of separate discourse.
BETTER THAN GoID-OSE HUNDRED Lors
NEAR DENVER, COLORADO, FREE.-Desiring to
advertise our new addition extensively we have
concluded to give away 100 more choice lots
We will also sell 200 very choice lots at "a
each and 100 corner lots, 50xl25 feet, for 50
each, provided all orders for same are in by
February 20. The lots we giving away and
selling are in Plainfeld, a new suburban addi-
| ton on the Fort Worth and Denver railroad, q
few minutes ride from the Union depot at
Denver, Colorado, now q city OF 10000 inhab-
itants. All lots other than corner lots are 25x
| lbs feet Every purchaser will net 1000 per
cent IN one years time. We will not give but
We keep every other lot. Now Is the time to
get In II you appreciate the western idea OF
booming. A grand barbecue and auction sale
of lots in June. II you desire a free lot send 4
cents for postage. Purchasers remit bank drafts
or registered letter. We refer by permission
to Judge ]. II. Craig, mayor Of Castle Rock.
Address Plainfeld Addition Company, Castle
! Rock, Colo.-Adut