The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1879-08-18

platform of the car. containing FIVE cubic feet or
water drawn from stationary boiler under on
pounds pressure and having a temperature OF 32S
degrees The action OF the heated water on the cool.
dry compressed air will be made clear by the follow
ng:ro raise the temperature of one pound OF water
from 80 degrees to 22 degrees requires much heat
as would raise % pounds of air through the same
range. The specific heat of air compared with
water being .2.377 to l. pound of air increases
III volume by heat from 1887 cubic feet at "
degrees to 1928 cubic feet 1928 degrees which is
an increase OF 1886 cubic feet 1t is held by the in
ventors that by the use of the water at such high
temperature the effect power OF the compressed air
can be doubled There are many improvements in
the machinery that are worth stating. One is the
cylinders are arranged that they made to act
as brakes when descending steep grades. Mr..
Hardie, one OF the inventors. informed the HERALD
reporter that in running down grade on the Second
Avenue Railroad the pressure even increased in
the receiver pounds in about one-hfth of u
mile. being pumped back by the piston. The action
of tho cylinders as brakes is marvellous. Although
travelling at the rate Of about thirteen miles an
hour Mr.. Hardie brought the motor, in which the
reporter was sitting. to a full stop within its own
length. On asking the inventors to what the
relative cost OF the running of the motors would
be. compared with that of the locomotives tho
elevated railroads, they said that they run an
average two hundred and seventeen miles on two
tons and one-haf of coal which is about two pounds
and half per horse power every hour. and they
believe that the elevated railroad locomotives
work under twelve pounds of coal per horse power
every hour. Again. the locomotive requires the
services of an engineer and stoker while each motor
needs only one unsklled man to drive it, with only
the addition OF about twenty-five cents per day as
pressing engine. The inventors further stated that
pumping plant, capable OF delivering $40 cubic
feet OF air at the pressure OF $50 800 pounds
square inch per minute could be erected at the cost
OF about $4,000. Such engine would be suf-
firient to despatch every quarter of minute to
run ten miles. The same engine would I'LL an
elevated road motor in minute to run with
train Of three or four cars distance of twenty
miles The cost of this air COMPRISING machine
would be less than that of ten locomotives on the
Sixth avenue line. which. IL is sad cost 81 500 each,
and the expense OF running it would DO considerably
O
use OF the pneumatic motor on the surface roads
would be the taking away OF the large stables which
are terrible nuisances on account OF the enormous
accumulation OF filth that necessarily occurs about
them. By doing away with those large buildings.
that crowded with many thousands OF horses. it
is the opinion Of many prominent physicians that
great sanitary improvement would be made
WHAT THE ELEVATED ROAD AUTHORITIES SAY
Mr. Baird. of the Metropolitan Elevated road. was
asked recently whether the question Of using COM
pressed air the elevated roads had been consid-
cred by the directors officers. and if what OBJ
jections had been found to it's use.
He first inquired very carefully to the extent to
which the Second avenue road using it. and then
said that he had been familiar for many years with
the Of compressed air. and did not think that it
had been fully developed 1t was used successfully
he sad in many places where it was incoRvenient to
stea as in mines and 1t was used for operating
drills, but there obstacles in the way Of its
in large engines that had never been overcome. The
machinery used had been greatly improved. but
there still great for Improvement At
present it not in any such condition would
warrant its adoption by the elevated roads.
"Could it not be tried experiment % asked
the writer.
..The officers of the elevated roads," replied Mr.
Baird. "think that they not justified in trying
experiments their roads. II we should run an
experimental engine roads and it should break
down in any way. or IL the supply OF power should
give OUT the whole road would be blocked. and the
public would be greatly inconvenienced."
There is place where more inconvenience would
be caused by the failure OF an experiment than
our roads for If train is stopped we cannot pass
by it, and the block is absolute 1t would be trfng
with the public to try it. We must have something
that We can rely upon-something that will not give
out and something the rules of which are thoroughly
understood. In other words, must know what
engine will do under all circumstances before
use it,
''rhen you try experimental"
"None. There is no place less adapted to the pur-
pose than our roads and there is every chance for
the thorough testing OF any invention of the kind
before it is put our roads without tho inconve-
nience that would attend failure there. Almost
every day people come here with devices Of different
kinds which they want us to try They propose
caloric and vapor and coal oil and the generation Of
steam by acids and all sorts OF different things, and
they perfectly willing to have try them. We
might perhaps. get something or other that would
be very good at u small price II We could buy it and
develop 1t, but prefer to wait until 1t has been
tested elsewhere ii have to pay more for It,
People who not well acquainted with tho details
of mechanical application do not realize ut least
they not apt to realize, that the conception
OF idea is very small part of what has to be done
to put it in nse The machinery has 10 be designed
built tested and generally altered before tho idea be-
comes OF practical value.
Compressed air, T" he continued, "has to be forced
into reservoirs by machinery and this operation has
been found to generate great deal OF heat This heat
they dissipate in the OF small engines by
sprays of cold water. but 1t would be very different
thing to keep the heat down in large engine. This
is simply of the difficulties in the way of using
1t large scale. People think that because thing
have to do Is to enlarge the machinery to make it
work well on large SCALE but this is not so. Now
a great many people have believed that great deal
could be done with caloric. Captain Ericsson had
that on his mind for number of years, and he did
q great deal toward making it useful, but it
found that while it worked well up to five six
horse power they could not get ten horse out
OF it. Calorc. believe. has boon developed to its
limit. but do not think the same proposition holds
true in regard to compressed air. do not believe it
has been developed to its limit by any means. And
/ do not believe that 1t has been brought to that
point which it would be sorviccable roads.
do not know that the Second avenue people have
yet train their entire route. Now 1t Is
thing to a single a short distance. and It
is quite another thing to run one OF our trains
the entire length OF our route"
But said the writer "if the idea Is demonstrated
to DO practicable. would 1t not be likely to DO
adopted by the elevated roads, as doing away with
smoke. gases. &c.y'
.'If the idea proved to be practicable said Mr..
Baird. I've shall be glad to adopt 1t, but up to
the present timo wo do not understand that 1t has
been"
IJRIJGIIAY