The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1899-03-25

more perfect forms % Eas cnEias asd
compressed air motor. tt u a tcco<-
nized fact that the system % indie
pendent motors j. the one that sscat-
ualiy will BE- adopted. one great rCa-
son for this is that The machine Viii
| be free % losses due to transmission
and can b, operated a. long az its
charge lasts. The loses due 60 trans
mission are far greater in slcctrtr
than ia compressed air lines. There
u one important difference b. .Necu
electricity and compressed air. In the
transmission OF a given power by clcc-
| tricity under a given pressure. the
weight OF copper will increase az th.
square OF the distance. while With
compressed air. the cost 10 the pipe
will be directly proportional to- the dis
lance. In other words: one hundred
miles Of electric transmission would
require ten thousand times the weight
OF copper OF one mile. whereas. with
compressed air. one hundred miles
would require but one hundred times
the cost OF one mile for an equal
transmission capacity Of tko pipe.
There are many points OF rcscmb-
lance. rs we'll rs difference. between
electricity and compressed air that
have not been generally known. IL g.
well known fact that for economical
electric power transmission very high
voltages must De USED. say from ten to-
fifty thousand volts. and at the term
mus. step-down transformers are -
quired to bring the pressure down for
safe distribution and use to FIVE hun
dred volts or less. IL was not until
recently recognized that compressed
air can be transmitted long distances
economically only at high pressure.
say OF 1000 to $500 pounds per square
inch. and that u also must be- reduced
ut the teTminus-to about $50 pounds
to be economically utilized in the var
ious forms Of air motors.
Nothing has been said above regard
ing the use OF water power. which can
be used TO run either an electric gen
orator ar an air compressor. ON &c
count of the greater economy Of COM
pressed air transmission. Il comes to
the front not only as competitor. but
as an aid to electricity. II power can
not be transmitted long distances safe
~ ard economically by electricity. Il
can by air. and the power thus trans
united can be used locally to generate
electricity for heat. light and other pur-
poses. and In addition. the compressed
air can be used for refrigeration and
ventilation.
| On account OF the vaStneSs. Il is i'm
possible, in so few lines. to give more
than a smattering OF this subject. To
make scientific comparison would re-
suit in n large number OF complicated
formulas. Suffice to say that COM
pressed air. like electricity. Is SUCCESS
fully driving thousands OF machines:
bu; regarding economy. safety and
simplicity Of operation. compressed
air Is now in the ascerdancy.
Statements have often been made
that in Paris the compressed air Sys-
tenn has proved n failure and that great
losses had been sustained by the in
vestors. This Is not n fact. but allow
ing IL to- be so. the reply - that no one
has right to- expect great success
where the essential conditions in COM
pressed air power transmission are Vio-
lated. All attempts heretofore at
power transmission have been made at
low pressures OF from co to zoo pounds
per square inch. but as the loss of pow
er in transmission under n given
weight OF air at 200 pounds. initial
pressure, Is ten times rs great rs II the
pressure were 1000 pounds. IL can read
lily be seen why great success has not
hitherto been attained. Ignorance.
prejudice. and the large amount OF cap
ital invested In electric manufacturing
plants ard apparatus have retarded
the recognition and universal adoption
OF compressed air as the most econom-
ical and efficient agent for
the propulsion OF street cars
and automobiles for city ard su-
burban service. as well as the trans
mission OF power to great distances.
IL can he successfully demonstrated
that the power actually utilized in foot
pounds in the cylinder OF an air motor.
Is largely in excess OF the power sx-
pended in compression. and that air.
under high tension. can be transmitted
tn very great distances with no s!imu-
milton whatever in the amount OF cork
that IL Is actually capable OF perform
ing. This last statement generally
prOyOkCs a smile OF incrcdulity. bat
the explanation lies in the perfection
OF the simple and efficient modern air
reheatCr. The volume OF one pound %
steam At atmospheric tension O. IS
cubic feet. hence when steam - used
for heating the air. IL adds more than
80 per cent to the volume OF air adm 4
ted into the motor cylinder: but the
air Itself. by increase OF temperature.
Is also expanded more than 50 per
cent. Thus the volume % the air "a
increased more than leo per cent az a
temperature OF $50 degrees. In other
words: by the simple process OF re-
heating. less than one-half the weight
OF air would do the work than u the
air were used cold and dry. The cost
OF the reheating Is triainE and requires
but a few seconds.
Nearly all the large cities OF the
United States have witnessed the evil
effects OF the overhead electric trolley
system. The beauty OF their streets
has been impaired. Loss OF lfe and
property has been great. Great ex-
pense has been incurred BY the electro
lytic Tor eating away actio7 OF the
trolley currents upon the water and
gas piping. Owing 20 the large amount