Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1882-01-14

OioSOQ fSSSci, we have u lSSiuuc VI
charcoal or boneblack, which is composed
principally of carbon and phosphate OF lime.
| Phosphate of lime is one of the most valua-
bic of fertilizers, and boneblack is therefore
largely used by agricultHrists as dressing
for their lands. Boneblack is extensively
used in the refining of sugar, where advan.
tage is taken of the remarkable power
which charcoal, and particularly bone char
coal, has of absorbing gases and coloring
matter. Ignite and coke compose the
hard, porous and lustrous residue left when
bituminous coal is heated in limited sup
| ply of air, as is done in the manufacture Of
coal gas. This residue is composed prin-
cipaliy of carbon, but contains some incom-
| bustible matter, besides more or less
oxygen, hydrogen and nitrogen n. The
| temperature at which carbon is
formed, and It's origin, regulates the
| degree of hardness and the porosity Of
the product. Carbon Is, unless heated to
very high temperature, very indessructi-
bic; this accounts for the difference be-
tween the keeping qualities of eharred and
unchaTred woods. Carbon may be re-
garded as the characteristic Ingredient of
all organic compounds, for there is no
single substance that is the exclusive re-
sulG of vital organization, no Ingredient OF
the animal or vegetable, produced by their
growth. that does not contain this ele-
ment While carbon ia a solid and recog-
nized by the senses of sight and feeling.
| oxygen, which we will next speak of, is
invisible, odofless, tasteless, and, by the
unassisted senses, can not be distinguished
from ordinary air. Oxygen is gas exist
ing in the tree state in the atmosphere. 1t
can only be obtained pure, however, by
extracting 1t from some OF its compounds
that is to say, it can not be separated from
the air by mechanical means. Many
metals unite with the free oxygen IN the
air, forming compounds which, on being
heated, give off the free oxygen. For in
stance, if mercury is heated for some time
it is converted into a red anonymous pow
der, which, on being more strongly heated,
decomposes with the liberation of the
oxygen which it had distracted from the
atmosphere the residue left Is found 10
he pure metallic mercury. Oxygen is most
conveniently prepared by heating potas-
STUN chlorste, white powder which can
be procured from any drug store. As oxy-
gen makes no sensible impression on the
senses, we can only distinguish 1t by noting
it's behavior toward other bodies. 1t Is
the grad supporter of combustion, and ali
ordinary cases OF burning are nothing more
than the chemical combination of oxygen
with some other body. Heat and flames are
the products of this chemical combination;
hence it is evident that fire and combustion
are simply the rapid oxidation of matter.
The rapidity of combustion is directly pro-
portional to the amount of oxidIzation
which takes place in given time. The
blacksm with his bellows forces stream
of air into the fame, and thus increases
the supply of oxygen and the intensity OF
the heat. The amount Of heat given off by
burning given amount of matter is con-
slant, and is independent Of the rate of
consumption. No more heat is got by
burning log OF wood than is given off
from it during the natural process OF de-
cay the only difference is that by burn
ing the heat is ali given off in a few hours
with great intensity, whereas by decay
the process goes on, maybe, for years, and
the heat, being given off gradually is al
most imperceptible. The air is composed
of a mechanical mixture of about one
part of oxygen and four parts of
MT 'og' n Tau element of which we will
speak later ou). The distinction must be
understood between mechanical mixture
and chemical combination. A mechan-
ical mixture is simply compound of two
or more bodies, in which they retainstheir
individuality. i. e., their SIZE, shape and
properties If you mix salt and sugar,
or sugar and water, you have me-
chanical mixtures, in which the indi-
vIdual properties of the compounds re-
main unaltered. On the other hand, a chem
ical com bnation is the mixture of two or
more bodies accompanied by chemical
action, and in which the bodies lose their
ideality in new compound, which IN most
cases bears no resemblance to either of its
constituent elements. If you pour water
over commercial lime you have chemical
combination accompanied by intense heat
or if in solution of bluestone (sulphate of
copper) you put a piece Of metallic iron,
the iron will appear to melt away, and you
will find particles of metallic copper in the
bottom OF the vessel, which you can prove
to be copper by burning IN the fame of an
alcohol lamp, IN which case the flame will
be colored intensely green. In this reac-
ton the iron has taken the place of the
copper in the sulphate of copper, and you
now have a solution OF sulphate of iron
and metallic copper. This process is made
use of on large scale in getting metallic
copper from its ores. The ore is first
burned and then treated with sulphurc
acid foil of vitrioI, and old iron is
added directly to this solution. The pro-
duct is the unrefined copper cement Of CON-
merce. Oxygen is very active that is, it
combines very readily with the normal
temperature Most all of the metals will
oxidize if allowed to stand in the open air,
and especially if the atmosphere is moist.
Iron rust is simply an oxide of iron, and
the furnishing of freshiy.cut lead is due to
the action of oxygen on the clean surface
of the lead. The atmosphere contains
about the only free oxygen in nature it is
composed of about one. fifth oxygen. Be-
sides this abundant supply in the air, oxy-
gen in chemical combination with other
substances comprises about eight -ninths of
all water, and one third of the solid crust
of the earth, and of all the plants on the
earth. 1t may be easily seen that oxygen
is the most abundant of all the elements.
The presence of oxygen is absolutely
necessary to organic life. In animals
| it Is introduced into the lungs in
the act Of breathing, when it
aids respiration. It has been called "vital
air for the reason that plants and animals
soon die if the supply of oxygen is cut off
The reverse is almost as disastrous to ami.
NAL life, for in an atmosphere of pure oxy-
gen animals would literally "burn up" in
very short time To guard against this
too rapid combustion, nature has wisely
diluted the oxygen by mixing with it
another element nitrogen. Many of the
metals will burn in pure oxygen. If you
tip watch spring with sulpher, ignite the
sulphur and plunge the burning end of the
spring into jar of oxygen, the spring will
actually burn with bright sSintiilations,
until it is all oxidized or consumed. The
common jewellers blow-pipe is meant to
intensity the heat of a flame by fore
ing air into it, thus supplying an
extra quantity of oxygen. BY means of
the oxyhydrogen blow pipe We can get a
still more intense heat. With this instru-
| ment. instead OF forcing a let of air into