The post. [volume] (Middleburg, Snyder County, Pa.) 1864-1883, 1879-07-10

II subjects were considered i'm
portant in proportion to their utility
heat would have been among tb,
first objects Of human interest But
unfortunately, this has not been th,
case. Those questions that affolt
qualification to the imagination, unt
speculation to the un understanding
have absorbed the attention of m IN
kind in all ages. The poet, Philoso
pher, legislator, aud divine, each IN
his turn, has frequently lent his aid
to subjects of puroly speculative
and imaginative nature while til,
great agents that develop the resour
ces Of nature, and afford health, hap.
piness, and progress to mon, have
been almost entirely overlooked.
Hence, in accordance with this spirit
OF human inquiry, poetry, eloquence
rhetoric, and speculative philosophy
have received u large share OF inves-
tigation. And it is u significant fac,
that cur best poets, rhetoricians, and
theoretical philosophers, are to be
found among the ancients. We have
advanced in these subjects little
since the days of Aristotle. In phys
ical since, however. the moderns
have achieved wonders truely worthy
of the age. Heat is purely quality
Of physical bodies, aud exists with
out known limit in all. II is impon.
derable and invisible, aud known on
ly by the effect it produces among
material objects. 1t plays mos,
important part in all the various
phenomena of nature. No body
whether organic or inorganic, exist
without somo degree of heat. Next
to gravi,ation, il is universal 10 all
material bodies. Tho most inert
and rude masses ar pregnant with it.
Whatever we feel, touch, taste, on
smell, is full of heat. All the forms
that boaulify the surface Of the earth
owe their existence 70 the inilaenc
Of heat. Without its genial power
all nature would be notionless, and
in profound ropose-all suddenly
fall into solid, impenetrable, form
less without order, without
beauty and it may DO Significantly
sail "chaos reigns again. or the
ultimate nature of heat we know
nothing. II exercises, however, q
most important function in all the
process of nature. But, like Gravl.
taticu, which pertains to all bodies
it is properly known only by It's
function. Heat is called IA imppu
dorable agent, because it has no sen
sible weight. Like light, 1t has laws
of radiation, transmission, reflection,
polarization, absorption, and rufrac-
tion Uaat pertains t. the intimate
particles Of matter, or molecular
imposition, as well as to thor ag-
8rogition. lleuco it 10 rs importlut
IN the sphere Of Chemistry MS that .!
natur.l philosophy. By theapp!ica-
ton Of hoat t. II compound body the
most stubborn aili lilitios are brokon
up, AMI the body reduced to its ul-
timate elements. Hoat is indi'pau
sible to tho elaboration aud growth OF
all organized bodies. aud the most
necessary agent in their composition
and decomposition. Nutlition can.
not tako place without n sufficient
degree OF heat. Warm blJodel AMI
NAL bodies require niuety-eight do
grees of heat aud a temperature
but five degrees below this would be
incompatible with life-the functions
of life would cease Heat being thus
indispensable as au element in al
material bodies, the next inquiry
will be its source, laws, and pheno-
mena. "rhe sources of heat are
chiefly, the SUI, combustion, chemi-
cal changes, friction, electricity, vi
tality, and lastly terrestrial radiation.
Solar heat accompanies tho suns
light. and most unquestiouably re-
suits from tho intensely high tom
perature Of the sun,or atmosphere o
the sun itself. Combustion, or in
tense chemical action, is also accom-
panied with the elevation Of heat
Friction causes heat as u result o
mechanical motion. Thus, in boring
a cannon under water, heat evolves
sufficient to bring the water to /
boiling point, and largo buildings
may be warmed in this way.
Terrestrial radiation is constant
source of heat. Geological investi
cations have proved that tho contre
Of the earth is in q liquid state, anC
the surface has gradually cooled tc
it's present condition. Hence th'
earth is source of heat to itself. i
has constantly thrown off heat from
this source for thousands Of years
The intense heat of the earth II
proved by the progressive increase
Of heat as we descend into its inte
rior.
The deepest we'll known is TIVE
thousand two hundred feet, and ii
water has temperature Of ninety
one degrees. The average increas'
of temperature, rs We decend, is owe
one degree to every ono hundred
feet. At this ratio we will have, a
two miles, the boiling, and ut twen
by three miles temperature OF a
bout two thousand two hundred de
srees. At this heat east iron, tral
md rocks. and nearly all solid bod
! les, are in fluid state. Hence "
san easily account for-the pumerou