Burlington free press. [volume] (Burlington, Vt.) 1827-1865, 1836-12-23

called by the name of Oxygen, aud nearly
makes up the remaining fifth part of atmos-
phorlc air. In its support OF life 1t always,
and in maintaining combustion often unitcs
with a chemical element, which is called
carbon. This is Familiarity known as form
| ing the principal part of charcoal. In It's
union with carbon, oxygen forms peculiar
gas known by the name of carbonlc acid.
| Carboninc acid is always found in small
quantities in the atmosphere, to which it is
| furnished by he breath of animals and the
fumes of burning bodies. It is, when IN
! considerable quantities, fatal to the life of
| animals but is prevented from accumu'a-
| ting to an injurious extent in consequence
of its being taken up by water; it is there
! fore dissolved. in proportions about equal
to those in which it is formed, by rivers,
| lakes, the ocean, aud the moisture of the
soil.
Water exists in the atmosphere in The
form of vapour. The great source of this
vapour is the extended surface ofthe ocean;
and it is governed by mechanical law. by
which it is continually tending to distribute
itself uniformly over the whole surface Of
| the earth. 1t may thus exist in as large
quantities over the surface of the drvest
| land as over that of the ocean itself This
tendency to equal distribution is continually
coun,eracted by the changes in The sensi-
bic heat Temperature of the atmosphere,
and of the surface Of the earth, which FOL.
| low the alterations of day and night, and
vcssitudes Of the seasons. By these al
iera'lons aud changes, the vapour is caused
to fall (precipitated) in the form of rain,
snow, hail. dew, or white frost. according
to circumstances. As such changes OF
'emperature are more frequent on the land
than on the ocenr, the water which falls
on the former in either Of these is greater
in quantity than that which falls on equal
surfaces of the latter. Thus, by wise
! and benevolent provision of Providence,
the water of the ocean is continually fur
nishing vapour, which is preciptatcd on
the land for the support of vegetation and
the supply Of springs, and whose excess is
poured back into the ocean in streams and
rivers.
Water has been found by chemists to be
a compound substance, made up of two cl-
emenls. One of these. which forms g. 9ihs
o! its weight. is the gas already mentioned
under the name of hydrogen.
! Hydrogen, when free is the lighte2t OF
all known bodies. rising or floating in at
mospher!c airs it not only combines with
oxygen. 10 form water. but with GORDON to
form great variety Of mponnds-gase-
Gus, liquid. viscld. and solid. II also com
hines with nitrogen, and forms gas known
bv the name of ammonia, which is well
known by the peculiar smell II gives TO
spirits Of har'shurn iiiquW ammonia
Hydrogen also combines with sulpher,
forming a gas known by the name of sul
phuretted hydrogen; this exists in the al
mosphere. bot in such small quantities as
only to be detected by The incest chemical
tests. l. combines IN like manner with
phosphorus. forming phosphoret,ed hydro
gen gas, whose presence III the air is oc-
I casionaI'y perceptble.
Oxygen. as we have seen unites with
carbon to form a gas, which we have called
carbonlc acid
! This receives the latter part of its name
from lis similarity in properties to an ex
tensive class Of compound bodies, known
by the name of the .Acids. The great r
part of these, like carboulc acid, are com
hlnations uf lutiammabe bodies with oxv
gen. Tie most lmportan, of these in ref
crcnce TO our present object, are the sui
phurlc and phosphoric acids; named from
the two substances Sulphur and phospho
rus which are their bases.
Muriatic acid may also be mentioned
here. although ITS composition is of DIFF
fercnt character. Oxygen, united with
other bodies 10 form a class of composition
IS of different character. Oxygen uniles
with other bodies to form a class of COM
pounds known under the ngme of oxides.
: The acids unite with earths, alkaes
and metallic oxides to form class of com
pounds known under the general name OF
} salts. These are named from The two sub
stances which enter into their composition
thus, the salt formed of ulphurIc acid and
; the earth lime, is called sulphate of lime
The substances which unite with acids tC
: form salts. are called the basis Of the re
: speclive salts.
, or these bases, the alkalies and earth:
are the most important. OF the alkalis
, it is only necessary to know the names o
two, namely potassa and soda, and to be
aware that their distinctive properties, are
, to possess an acrid taste. causlic opera
ton, to render oils capable of mixing will
"dltI, dUu " HGulIuhLc Tue pTOptIllGS U
acids,
: The earth which chemists call by tn,
name of slick or silica it is also most pur,
in flint and rock chrystal; it is also Amos
pure in sharp colourless sands, and is b.
far The larger part Of sands ofevery descrip
ton. So tar as the farmer need know ii
properties: it is hard rough to the touch
has no attraction for water, which it per
mlts to filter through, or evaporate from i
) with the greatest ease. 1t is capable q
! uniting with the other earths IN com
pounds which are called silicates, and i
, the only earth which enters into the forma
, ton of soils uncombined with the others o
with other elements.
; The earth which chemists call by The
name of aiumina, is so named because It i
} obtained by them in pure form from tn,
: well known salt called alum, of which it il
the basis. Its most marked characteristic,