The Davenport daily gazette. [volume] (Davenport, Iowa) 1856-1869, 1857-02-03
Mnsas, Epsroas:--

- ieet tiss vaeesee.
AossSs skatin lsts
number yoa mention q AstrssSs fact that |
the mercury indicates hnpsrasurs ssns |
two degrsssen ~ blals and fssf dsgssss
on the csaepl ~ u The lrides AgAsr dan |
IN town.
This woeh ssen ssrases wAn We EN-
slider that bah els situations u1oh sxpessd
to winds, but ! think Il can b accounted
for on nataral principles, and b therefore
-isst what ~ might szpsct.
Il is we'll kaown that sir u sxpapdsd and
nads lighter By heat, therefore the coldsst
cir must b the most dcasc, and otksr taiass
bsise Qssl viii sisk to tho lowest lsvsl.-
Bot 10 ascending high mountains Or in bal
looms, o. descending iato the earth, We fnd
that this law does not hold good. and for
rsasons which il will make this communiea-
ton too long to explain. lis . common
remark In billy New England that Il freezes
much harder In the valleys than On the hill
tops. The diosrssse Of Temperature be.
tween the top and bottom Of room can
sssily - detected BY the hands, and It 10
pleasing experiment to open door between
. warm and cold room. and hold lighted
lamp In the doorway; BY holding II 1t the
bottom 1t will - sssn that there 10 strong
current Of seA cir iate the roam; this, being
heaviest. displacss the warm siE which
rushes 81 At the top. while midway be-
tween top and bottom it will be seen that
there b no current at oil.
| Now for the pier; il has been clearly
proven that freezing is heating and thaw-
| ing cooling process. y the ceasrac,ion
that takes place before wstsr reaches the
freezing point. large amount Of latent
csloric 10 given Of which 10 communicated
to the air and raises IL temperature. Much
more il given Of whom vapsr u condensed
to water, q there d . much greater dimi-
mutton in bulk. This 10 the reason why il
10 warmer Immediately after storm Of rain
or snow. On the other hand. when ice 10
converted into water or water into vsPor
there 10 great demand for heat to supply
the amount which wster and yapor mas
contain in lssest ststs, and this it borrow
from the atmosphere. The following are
familiar examples Of the two processes;
| Place large vessel Of water in cellar
where vegetables have been frozen. and il
| will be found that (unless the cold Is very
seyere) the vegetables will not freeze. Al
they are protected to some extent BY their
outer covering the water will freeze first
and BY this means the temperature 10 raised
30 niue b that they viii net bstrozen.
When ice OF snow arc mixed with salt q
chemical union Jake. place which produces
liquefactien. and 20 much heat b sbstracted
from substances with which they are in con-
tact. that they are frozen very quickly, a.
in making ice e,esm.
Now during most Of the days and nights
Of this winter We may suppose the freezing
process has been going on in the river,
which, l think, accsants for the higher tenn
perature at the pier.
According to this theory We may expect,
LII the snow il melted and the ground be.
comes dry before the Ice goes out of the
river. that the temperature will be several
degrees losOer at the pier than on the land,
and prophecy that this will Be the case,
not only then, but through the warm sea-
son, and that it will never be higher al. the
pier except when il 10 below the freezing
| point. We shall see.
Yours truly, F.J.S.