The Sun.
London, England, 1858-12-30 00:00:00

LITERATIIRE.

Curiosities of Science. By John Tinibs,
author of " Things not Generally Known," &c.
Ker,t and Co. .

This is another of the little treasuries of knowleuP
which Mr. Timbs offers to the public in this 101)re:
tending form. The present volume fully maintain"
the character of those which have preceded it;
indeed, in some respects it surpasses them. 3,1 r.
Timbs rightly calls it a book for old and young, o
there are few readers who may not learn somer
thing from it, while the succinct and simple manlier
in which the marvels of science are familiarly'.
explained might well attract the most superfleia
or indifferent reader. To the large class who are
unable from press of business, and want of leisure_
to prosecute scientific oldies, this little volulo,
will be invaluable from the variety and extent ();
its information, and the clear and condense;
manner in which it is given. We subjoin afe
samples :

" THE UNDULATORY SCALE OF LIGHT.
"The white light of the sun is well known to be comP°'
ed
of several coloured rays ; or rather, according to the then l
of undulations, when the rate at which a ray vibratestre
altered, a different sensation is produced upon the 19P,.
nerve. The analytical examination of this question
that to produce a red colour the ray of light must 0,,'"
37,640 undulation in an inch, and 458,000,000,000,000 i;;
second. Yellow light requires 44,000 undulations in t
inch, and 535,000,000,000,000 in a second ; whilst thee
of blue results from 51110 undulations within an inch, 33„
622,000,000,000,000 of waves in a second of time."----iaN"tl
Poetry of Science.

" VELOCITY OF LIGHT.
" it is scarcely possible so to strain the imagination as
611710'
conceive the Velocity with which Light travels. brl
mere assertion will make any man believe,' asks Sir Ja,
Herschel, that in one second of time, in, ene beat of t 2,1
pendulum of a clock, a ray of light travels over 192,7 d
miles ; and would therefore perform the tour of the '
in about the same that it requires to wink with our eyelids
and in much less time than a swift runner occupies , •
taking a single stride ? ' • Were a cannon-ball shot direr
towards the sun, and were it to maintain its full speed'
would be twenty years in reaching it ; and yet light trace
through this space in seven or eight minutes.
The result given in the Annuaire for 1842 for the
velocity of light in a, second is 77,000 leagues, which
responds to 215,834 miles • while that obtained at the
kowa Observatory is 189,746 miles. William Richardsof
gives as the result of the passage of light from the sun' of
the earth Bm. 195..28, from which we obtain a velocity /
215,392 miles in a second.—Memoirs of the Astronowica
Saeiety, vol. iv,.
" ALL THE SALT IN THE SEA.
The amount cf common salt in all the oceans is eg„
mated by Schafhautl at 3,051,342 cubic geographical ttl"ei;.
This would be about fives times more than the mass of t °
Alps, and only one-third less than that of the Himalar:
The sulphate of soda equals 633,644.36 cubic miles, or 1'
equal to the mass of the Alps; the chloride of rnagnesiuT'
441,811.80 cubic miles; the lime salts, 109,339.44 cleo
miles. The above supposes the mean depth to be but lh
metres, as estimated by Humboldt. Admitting.,
Laplace, that the mean depth is 1,000 metres, which Is lu'ie
probable, the mass of marine salt will be more than doub,
the mass of the Himalayas."—Seliman' s Journal, No. lu*
"Taking, the average depth of theocean at two miles, ati•s
its average saltness at 31 per cent., it appears that there!
de
salt enough in the sea to cover to the thickness of one of
an area of 7,000,000 of square miles. Admit a transfer;
such a quantity of matter from an average of half a ull;a
above to one mile below the sea level, and astronomers ,70
show by calculation that it would alter the length of t"
day.
" These 7,000,000 of cubic miles of crystal salt have gOt
made the sea any fuller."

46
ELECTRIC GIRDLE FOR THE EARTH. to
" One of our most profound electricians is repoi.--_.p
have exclaimed : Give me but an unlimited length of i'4;';
with a small battery, and I will girdle the universe witlf`or
sentence in forty minutes.' Yet this is no vain boast;
so rapid is the transition of the electric current along
:1,
line of the telegraph wire, that, supposing it were possi
to carry the wires eight times round the earth, the traol
would occupy but one second of time ! "

" CONSUMPTION OF THE ELECTRIC TELEGRAPIL
"It is singular to see how this telegraphic agencl.d,
measured by the chemical consumpt
dion of zinc and ale,
Mr. Jones (who has written a. work upon the Electric Tel
graphs of America) estimates that to work 12,000 rain.
telegraph about 3,000 zinc cups are used to hold the aci
these weigh about 9,0001b5., and they undergo decoral)°.st;t
tion by the galvanic action in about six months, so t 1„
18,0001bs. of zinc are consumed in a year. There arc a,';
about 3,600 porcelain cups to contain nitric acid • it rectee,
'4solbs. of acid to charge them once, and the charges re
46
newed every fortnight, making about 12,0001b5. 31i1"-
•
acid in a year."