Dodgeville chronicle. [volume] (Dodgeville, Wis.) 1862-current, 1866-10-25
Burning Of "a friction Match.

Among the varied operations of the arts
there is perhaps no other involving so many
chemical and physical changes, and so
many philosophical principles, as the burn
ing of friction match.
First in importance is the intense affinity
of phosphorus. for oxygen, IS it is this
property which makes friction match pos
sible. This affinity is SO strong that when
phosphorus is exposed to contact with the
oxygen Of the atmosphere at ordinary tenn
peTatures, the two substances combine slow
ly, generating light. which is visible as a
faint glow in the dark; and if the temper
allure is raised to about 120 deg. the COM
bination goes on with that rapidity which
we call combustion. 1t is easy to produce
this degree of temperature by friction
hence the possibility of the friction match.
1t is necessary, indeed, to modify the in
hammability of phosphorus for its use in
friction match, ard is done by mixing it
with little gum The gum also protects
it from slow combustion in the atmosphere.
The flame of phosphorus, though intense
ly hot, will not set fire to pine wood; it is
therefore necessary to interpose some sub
stance more readily infammable than wood;
the substance usually employed is sulphur.
Pine wood ignites at temperature of 600
deg, and sulphur at $50 deg. to 500 deg.
The phosphorus in burning kindles the
sulphur, and the sulphur flame sets fire to
the wood. F. 20
The refusal of the phosphorus fame to
kindle wood is fruitful of suggestions. The
quantity of heat generated by the burning
of any substance is in proportion to the
quantity of oxygen with which the sub
stance combines. One atom of phosphorus
in burning combines with five atoms of OK
ygen, producing phosphoric acid, P. o. 5.
The atom of phosphorus weighs 80 and the
atoms of oxygen 8, SO the proportion by
weight is 80 pounds of phosphorus to, 40 of
oxygen. Sulphur, in burning, combines
with oxygen in the proportion of one atom
of sulphur to two oxygen, s. O. 2, and as
the atomic weight of sulphur is Is the pro-
portion By weight is 80 Of sulphur to 80 of
oxygen, consequently phosphorus should
generate more heat in burning than sui
phur.
Again, this law is modified by either the
oxygen or the combustible undergoing
change of form in combining. If sub
stance is changed from the gaseous to tie
solid state, heat is evolved; if from the
solid to the gaseous heat is absorbed. Now,
phosphoric acid is solid, while suphurous
acid is gas. Phosphorus, in burning,
changes the oxygen with which it combines
from the gaseous to the solid form, thus in
creasing the quantity of heat generated !;
while sulphur, in burning, is changed from
the solid to the gaseous state, thus absorb
ing heat, and diminishing the quantity pro-
duced by the combustion.
These theoretical views have been con-
frmed by careful experiment. The results
obtained by Andrews from elaborate inves-
legations were, that one pound of phospho-
ruslin burning to phosphoric acid generates
sufficient heat to raise the temperature OF
5,747 pounds of water one deg centigrade;
while one pound Of sulphur, in burning,
raises the temperature of only 2, 220 pounds
of water one deg.
But it is not the quantity of heat that is
to be considered lii this case, but the inten-
Eity; which is in proportion to the quantity
contained in cubic inch or other given vol
ume. This, however, only increases the
difficulty, for the phosphorus flame being
condensed to a solid, while that of the sui
phur is ditfused as gas, the intensity of
the heat ought to be still more in favor of
the phosphorus than the quantity.
The usual explanation given for the fail
ure of wood to ignite in PHOSPHORUS
fame is, that the surface of the wood is in
stantly covered by film of phosphoric
acid, which protects it from combustion. AS
we have no better explanation to offer, we
raise no objection to this.
The products Of combustion, then, in the
burning of the match, are, first, phosphoric
acid from the. burning of the phosphorus
then sulphuric acid, from the burning of
the sulphur, and, finally, carbonic acid and
water from the burning of the wood.
This is far from being an exhaustive ex-
animation of the subject. The hydrogen
and carbon of the wood do not combine di-
rectly with the oxygen of the air, but the
wood first undergoes distillation, with the
production of several hydrocarbon gases.
which rise in the air and produce the flame
by their combustion; and after the wood
is burned the ash that is left behind il
made up Of some sixteen elements, com
bined with oxygen in various proportions
The activity of the burning also, is in
creased by adding to the paste some sub
stance containing oxygen which is held BY
feeble affinity, and which is, therefore
readily given up to the sulphur, phospho
rus, and wood. Among the substances EN-
ployed for this Office are saltpetre and tn
peroxides of lead and manganese. In com
plete examination of the reactions of tn
combustion, the decompositions of thes
oxidizing agents, with the resulting com
pounds or elements, would demand consid
GRAFTON All that might be said with rela
ton to the burning of friction matc
would fill large Misunderstanding Ane7
icdn.
Curious VVills--Oddities of HUI
man Nature.