|
Main
- books.jibble.org
My Books
- IRC Hacks
Misc. Articles
- Meaning of Jibble
- M4 Su Doku
- Computer Scrapbooking
- Setting up Java
- Bootable Java
- Cookies in Java
- Dynamic Graphs
- Social Shakespeare
External Links
- Paul Mutton
- Jibble Photo Gallery
- Jibble Forums
- Google Landmarks
- Jibble Shop
- Free Books
- Intershot Ltd
|
books.jibble.org
Previous Page
| Next Page
Page 77
_Sun's Appearance._--This was formerly supposed to be an even,
regular, dazzling brightness, except where the spots appeared.
But the sun's surface is now known to be mottled with what are
called rice grains or willow leaves. But the rice grains are as
large as the continent of America. The spaces between are called
pores. They constitute an innumerable number of small spots. This
appearance of the general surface is well portrayed in the cut
on page 92.
_Close Relation between Sun and Earth._-Men always knew that the
earth received light from the sun. They subsequently discovered
that the earth was momentarily held by the power [Page 270] of
gravitation. But it is a recent discovery that the light is one of
the principal agents in chemical changes, in molecular grouping and
world-building, thus making all kinds of life possible (p. 30-36).
The close connection of the sun and the earth will be still farther
shown in the relation of sun-spots and auroras. One of the most
significant instances is related on page 19, when the earth felt the
fall of bolides upon the sun. Members of the body no more answer to
the heart than the planets do to the sun.
_Hydrogen Flames._--It has been demonstrated that the sun flames
200,000 miles high are hydrogen in a state of flaming incandescence
(page 85).
_Sun's Distance._--The former estimate, 95,513,794 miles, has been
reduced by nearly one-thirtieth. Lockyer has stated it as low as
89,895,000 miles, and Proctor, in "Encyclop�dia Britannica," at
91,430,000 miles, but discovered errors show that these estimates
are too small. Newcomb gives 92,400,000 as within 200,000 miles
of the correct distance. The data for a new determination of this
distance, obtained from the transit of Venus, December 8th, 1874,
have not yet been deciphered; a fact that shows the difficulty
and laboriousness of the work. Meanwhile it begins to be evident
that observations of the transit of Venus do not afford the best
basis for the most perfect determination of the sun's distance.
Since the earth's distance is our astronomical unit of measure, it
follows that all other distances will be changed, when expressed
in miles, by this ascertained change of the value of the standard.
_Oxygen in the Sun._--In 1877 Professor Draper announced the discovery
of oxygen lines in the spectrum of the sun. The discovery was doubted,
and the methods used were criticised by Lockyer and others, but
later and more delicate experiments substantiate Professor Draper's
claim to the discovery. The elements known to exist in the sun
are salt, iron, hydrogen, [Page 271] magnesium, barium, copper,
zinc, cromium, and nickel. Some elements in the sun are scarcely, if
at all, discoverable on the earth, and some on the earth not yet
discernible in the sun.
_Substance of Stars._--Aldebaran (_Frontispiece_) shows salt, magnesium,
hydrogen, calcium, iron, bismuth, tellurium, antimony, and mercury.
Some of the sun's metals do not appear. Stars differ in their very
substance, and will, no doubt, introduce new elements to us unknown
before.
The theory that all nebul� are very distant clusters of stars is
utterly disproved by the clearest proof that some of them are only
incandescent gases of one or two kinds.
_Discoveries of New Bodies._--Vulcan, the planet nearest the sun
(page 138). The two satellites of Mars were discovered by Mr. Hall,
U. S. Naval Observatory, August 11th, 1877 (page 161). "The outer
one is called Diemas; the inner, Phobus.
Sir William Herschel thought he discovered six satellites of Uranus.
The existence of four of them has been disproved by the researches of
men with larger telescopes. Two new ones, however, were discovered
by Mr. Lassell in 1846.
_Saturn's Rings_ are proved to be in a state of fluidity and contraction
(page 171).
_Meteors and Comets._--The orbits of over one hundred swarms of
meteoric bodies are fixed: their relation to, and in some cases
indentity with, comets determined. Some comets are proved to be
masses of great weight and solidity (page 133).
_Aerolites._-Some have a texture like our lowest strata of rocks.
There is a geology of stars and meteors as well as of the earth. M.
Meunier has just received the Lalande Medal from the Paris Academy
for his treatise showing that, so far as our present knowledge can
determine, some of these meteors once belonged to a globe developed
in true geological epochs, and which has been separated into fragments
by agencies with which we are not acquainted.
Previous Page
| Next Page
|
|