Staunton spectator, and general advertiser. [volume] (Staunton, Va.) 183?-1849, 1845-12-04


with nitrogen, tho form in which il exists i'm o,
+ atmosphere, that 1t Is best adapted to the suppo
/ OF HE. Plants as well as animals cannot liz
for any great length OF time if deprived of OK,
gen, and yet die Ia AN atmosphere of pure OK,
gen.
9th. oxygen is one of the best supporters ,
: comous'ion with which chemists are acquainte,
All substances which are Capable of burning i
The open air, burn With far greater brilliancv i
oxygen. piece of wood on which The leas
spark Is visible, bursts into fame the mon,en
u Is put into jar of oxygen :-phosphoru
burns with 80 dazzl9g light that the eye ca
hardly bear IL. Even many substances which
: are not commonly reckoned among the conbusti
oies, such as iron and steel, burn rapidly in pur
oxygen.
} Oxygen can be obtained in separate condition
IN several different ways and from many diieren
rsnosianSrs. When we wish the gas perfect,
\ pure, we generally obtain'is from heyC hloro,e
fo'assa, by heating that salt TO a full red heat
when II Is not important 10 have it perfectly pure
II may be obtained at a much cheaper rate, b,
heating the Nitrate of Potassa, (Sai.petre) to ;
white heat In cast iron retort. In both of hes,
methods OF obtaining OXy gen, you have an ilustra.
! tion OF The law OF chemical affinity. As oxy.
gen is naturally gaseous substance, willis,
those with which II Is united in the cases before
us are mostly solids or liquids, the operation O.
heat Is TO reverse that OF affinity to unloose the
bands with which affinity had bound these ele.
menis together.
! CnLrt"e, like oxygen, exists at all ordinary
temperatures as gas, but unlike that substance,
! Ia has been made 10 assume the LIQUID for,n.-
ms change takes place under pressure of d.
bout 6l H. to the square inch. 1t is of a Yellow
ish green color, (hence its name from the Greek
word chdoros, green.) an astrn2en taste and dis.
agreeable odonr. 1t is about - times as heavy
as atmospheric air. Cold recently boiled water,
absorbS twice lis volume of chlorine, and Yields
IL again when heated for this reason, we collect
| 1t over warm and not cold water as we do most
other gases.
Among lis more important chemical properties
are the following, viz
ISL. 1T is possessed of wide range Of chemi-
Cal alhniies. uniting with most other simple
substances, producing in some cases true Acids.
and IN others, class of compounds strongly re-.
| sembllng the oxides. Its atomic weight is So,
AZ.
end. 1t destroys all vegetable and animal CO.
iorS and hence is use in The operation of bleach
ing.
5rd. 1T is incapable Of supporting animal life :;
ihdeed, IL is one oil the most suiiOcalIng of the
gases, exciting spasns and great irritation Of the
9ioiiis, even when diluted with air.
AN. Like oxygen, IL is supporter of combus-
non. In some Instances II seems 10 be better
supporter of combustion than oxygen :-phos-
ders, and copper in the form of thin leaves, take
hre spontaneously In this gas. In other cases,
/, VIII either not support combustion at ALL or
else VIII support ii but feebly. piece of burn
ing charcoal plunged into this gas is at once ex-
tiHguished; lighted taper in similar circnm-
stances, burns with small red flame and the
emission OF large quantities OF smoke.
c0mo"sf'on. Both oxygen and chlorine have
0een spoken OF as supporters of cumbusiion.-
nl1t,. a
lecture, Greet your attention To the nature of the
process TO which we give the name Of combus-
non or burning. Among the changes which ac-
company chemical action, (see y, Law of aifni-
w. Lee. ~ changes In Temperature were mem
TONED. All have noticed the effect produced up
on The appearance of bodies, by the accumula-
.ioh IN 'heh OF heat III large quantities. All So
iiu hooies begin 10 shine or glow in the dark AT
"A temperature of between 600 and 700 deg Far.
thermometer but this luminous appearance is
mol percepuhle in broad daylight before they are
heated To about 1000. The color OF this liphl
varies with the Intensity OF the hea, at first il
Is OF duil red, the redness becomes more and
more vivid as the heat Increases until AT length
IL changes 10 white, 10 the brlliancy of which
we can set no other limit, than that set by the
increase OF temperature which we can command
Liquids and gases are capable OF being rendered
req and whiie-hot as well as solid hodes-
combustion or burning is simply chemical
combination in which there Is a DEVELOPMENT of
sufficient heat 10 render the combining bodies
red or white-hot. When one of two bodies
thus combining is a solid, as in the case of pure
c"arcoai and the oxygen OF the atmosphere, The
combustion is without hame in The case before
us the rapidty of combination and consequently
me color OF the burning body. being determined
ny The supply Of oxygen, and hence the effect of
oioWlng Il. e. furnishing large supply of oxy-
GEM upon the color of the burning coal Where
all The bodies thus combining are gaseous as i'm
me burning OF d candle, for in this case the solid
'aHow Is decomposed and resolved into certain
gases before ii burns, the combustion constitutes
what we call fame. Where some of the burn
Ing substances are solid and some gaseous. as in
me case OF common wood, we have a mixture Of
The two kinds OF combustion. The degree of
neat developed by the chemical combination OF
substances varies greatly in the case of different
substances; but as general rule it is in proper
non to the rapidity OF their combustion, and of
course, TO The energy with which affinity acts
upon them. AS the operations of afIini " are
greatly modified ny several causes (see Law of
/ Chem. affinity, Lee. ~ we have, as general
ming, 10 bring SOME one or the other OF these
causes TO operate, where we wish To produce
combustion. The two TO which we generally
resort, Heat and Electricity mot that in. So
are The Immediate causes Of combustion, bat sim
ply That ihey remove certain Instructions which
before existed IN the way of the operation of af-
| Unity. 10 say then, that any substance is a
supporter of combustion, is saying nothing more
nor less than that it has powerful affinity for the
burning body.
On this general explanation Of the nature Of
combustion, we make the following remarks,
viz:
list. Nothing is destroyed by combustion
The material Of the piece Of charcoal which you
have seen bnrned to-day is not destroyed, it has
/ only entered into combination with oxygen and
the resulting compound is possessed Of proper
lies entirely different from those Of the coal, IS,