New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1918-10-06
Apparently Only 3OPer Cent
OF Gasolene Goes Into Power

10 the Automobile Editor of The
Tribune:
SIT: Few of your readers may care to
know what chemical action takes place
when the charge of gasolene is burned
IN the cylinders Of an engine, but an
intelligent user of an automobile ought
at least to know where to look for the
loss of energy which the gasolene he
buys has the capacity to furnish.
Many owners of cars have the idea
that the explosions in the cylinders
are not unlike those in cannon and
that the cooling water is necessary
but unimportant incident. But the i'm
portant difference between the cannon
and the engine is that in the case Of the
cannon the charge is in the form of
solid, which, by ignition, turns into
permanent gases, enormously increas-
ing the space formerly occupied by the
same atoms.
The reverse of this is the case with
respect to an exploded charge of gaso-
lene in an automobile engine. The
charge before exploding is wholly gas
eous, and it is fact that 100 cubic
feet of air and gasolene mixture will
WELD only SO Is cubic feet of the re-
sulting gases under the same cond-
tions of pressure and temperature. But
for the heat evolved by the chemical
reaction while the mixture is confined
IN the cylinder the chemical change
would actually diminish the compress
sion
Assuming a theoretically perfect pro
portion Of gasolene, vapor and air,
perfectly burned, the products sent
through the exhaust pipe will con-
slst Of seventy-four parts Of nitrogen
by volume, twelve parts Of carbon diox-
lde and fourteen parts of water vapor,
and OF nothing else.
The inert nitrogen, which forms by
tar the larger part of the air-gaso-
lene mixture, being about three times
as much by weight as the oxygen in
the mixture, is actually very use
tul element. Being heated it expands
with the other gases and utlizes in
this way the heat which the other
gases have evolved. 1t is therefore a
necessary part of the mixture, quite
as much so as the oxygen and gaso-
Iene.
The only source of power is the
heat so evolved. In order that the
machine may run and not burn itself
out, the cooling water is resorted to
and takes away some 40 per cent Of
the total energy theoretically availa-
Bile. Approximately another 80 per
cent is lost out of the exhaust pipe
when the exhaust valve opens.
The mere running of hot engine
does not necessarily utilize more of
the power. 1t is the amount of diff
ference between the highest tempera-
ture and the lowest temperature in the
engine which measures its usefulness
As the heat evolved is the only
Of n1,,.r ,.,i
produces only q fraction of the posi-
bic heat is wasteful.
One common cause Of waste is an
overrich mixture. An unduly rich
mixture contains too much carbon for
the oxygen air to combine with The
result in this case is that part of the
carbon particles become evident Is
solid carbon in the shape of smoke.
Part are deposited on the cylinder
walls, and others, Selling single
atom OF oxygen, produce carbon mo
noNlde gas, the. chemical reaction pro
duclng only moderate amount of heat
and the carbon monoXide gas Itself 6c-
ing capable Of further burning in the
presence Of additional oxygen, if il
were to be supplied.
In view Of the foregoing. the water
jacket and the exhaust pipe should
not be looked upon with indifference
as mere incidents of running the en-
CINE, but rather as items which require
study for their possible future elimi
nation and as channels through which
one loses two-thirds OF the virtue of
the gasolene which one buys. Never
eheless, they seem to be necessary in
cldents of the gasolene engine in its
present development.
A substantial saving in more than
one direction can be made if there has
been tendency TO overrichness in the
mixture. In these days Of economy it
should be the aim to secure a some
what lean mixture rather than to err
in the other direction. For economical
running the mixture should be not