of the gas situation is hard to say, unless it be that an inbred
prejudice against believing the word of any corporation has led to an
utter repudiation of such explanatory statements as may emanate from
time to time from the gas office. And it must be admitted that many of
the explanations are misleading, either through the intention of the
superior officials or by reason of the ignorance of their subordinates.
Hardly has the chill of shortening days driven us indoors in the early
twilight before complaints of poor gas become epidemic. Now, what _is_
‘poor’ gas? Is the gas deficient in light-giving constituents, or is
it merely burned in such a manner as not to afford a satisfactory
illumination?
The charter of Greater New York requires that the illuminating gas
supplied throughout the city shall be of at least twenty candle power,
or illuminating quality, or richness--that is to say, if we burn this
gas in a standard burner at the standard pressure (or at as near this
pressure as may be), so that the rate of consumption is five cubic
feet an hour, the flame thus produced shall be equivalent to twenty
standard sperm candles, each burning at the rate of one hundred and
twenty grains of sperm per hour, and all bunched--if such a thing were
possible. There can be hardly any doubt but that all the gas sent out
from modern gas works fulfills the above requirement. Indeed, my own
tests give results ranging from twenty-two to twenty-eight candles,
with an average of about twenty-four. Manifestly, the gas _sent out_ is
not ‘poor.’
Nevertheless, the fact that the gas as manufactured is of the required
candle power is no indication that the product as delivered to the
consumer will give a similarly satisfactory test. Distribution of
gas is attended with many perplexities, not the least of which
is condensation. The illuminating hydrocarbons, or light-giving
constituents held in suspension in the gas, are not so firmly fixed
therein as to be unaffected by the size of the pipe, the character of
the internal pipe surface, and barometric and thermometric variations.
The transmission of gas causes, therefore, a loss of candle power
ranging from a small fraction to several candles, although it is
possible to conceive of conditions so extraordinarily favorable that
the illuminating quality of the gas might be actually improved by
distribution.
It will be readily understood from this explanation that tests made
at the gas works, or even at points arbitrarily selected at a certain
distance from these works, are hardly calculated to satisfy the
consumer. For this reason I have preferred, in conducting these tests,
to sacrifice to some degree the accuracy that obtains in laboratory
experiments, in order to test gas samples _taken from the main directly
in front of the complainant’s own premises_. I argue that the consumer
cares little or nothing as to whether the gas as manufactured complies
with the law, or whether tests made at a point perhaps a mile away
from the works show the required candle power; but that he does want
to know what is the quality of the gas passing in at his service pipe.
The method of collecting and transporting to a laboratory the gas
samples enables one to say with positiveness that the gas at the point
of complaint has an illuminating power of at least so many candles,
and that it may be even one candle better than the tests indicate. The
figures thus obtained range from twenty and a half to twenty-five. So,
then, the gas _delivered to the consumer_ is not ‘poor.’
Hygienic reasons demand that the impurities in the gas shall not exceed
a definite percentage. Whatever effect these impurities may have upon
the candle power has been covered by the tests above explained, so that
any further consideration of these impurities may be omitted here.
It is always a difficult matter to convince an indignant householder
that the quality of the gas supplied to him is satisfactory. He knows
perfectly well that he is not getting the desired result, and no
explanation, however elaborate, as to candle power will placate him,
unless it be supplemented by a further statement detailing the cause
of the trouble. When you are trying to draw water in the bathroom
while the cook is filling the washtubs in the basement, do you say the
water is ‘poor’? Why, then, should you characterize the gas as ‘poor,’
when people nearer to the gas works than you are happen to be drawing
heavily upon the common gas main? Imagine, if you please, a long gas
main, with consumers tapping in at points throughout its entire length,
and with a gas holder forcing the gas in at one end. Since there is
a loss of pressure, caused by the transmission, it follows that the
pressure will be higher at the gas holder than anywhere else along the
line, the _difference_ in pressure depending, roughly, upon the size
and length of the pipe and upon the amount of gas flowing. Now, for any
one customer the size and length of pipe will remain constant, but the
flow of gas along the line will vary from hour to hour, consequently
the pressure at his house may be expected to vary from hour to hour.
The unit of measurement of gas pressure is that pressure which will
cause a difference of water level of one tenth of an inch in the two
legs of a V-shaped tube when one end is connected with the gas main and
the other end is left open to the outer air. Ten tenths, or one inch,
is the standard, or normal pressure.
[Illustration: EXHIBIT 1.]
Any appliance--even a gas-burner--operates to best advantage under
certain well-defined conditions. Depart from these conditions, and the
efficiency of the device is impaired to an extent depending largely
upon the nature of the appliance under consideration. For example,
burn an incandescent lamp at fifty per cent. above normal voltage and
it breaks down; burn a gas jet at two hundred per cent. above normal
pressure, and it still operates--how satisfactorily ‘deponent sayeth
not.’ Now, the gas-burner is supposed to operate to best advantage
at ten tenths of an inch. At this pressure the flame is neither so
wavering as to be affected by every chance draught, nor so rigid as to
permit the gas to blow through without being properly consumed. Below
the normal the flame decreases; above, the light is increased somewhat,
but not by any means in proportion to the increase in the gas flow.
Thus we see that the satisfactory employment of gas as an illuminant
depends upon the maintenance of a pressure high enough to deliver
the required amount of gas, but not so high as to cause wasteful
consumption.
[Illustration: EXHIBIT 2.]
Turning back now to the gas main, let us consider the pressures
actually existing. Exhibit 1 is a photograph of a twenty-four-hour
record of pressure at a point not far from the works. The radial lines
represent time, and there is a line for each quarter of an hour. The
circles represent pressure, there being one circle for each tenth of
an inch. Starting at _E_, the point at which the record begins, and
following the irregular line clockwise, one may readily determine the
fluctuations of pressure and the time of their occurrence. Interpreting
the diagram, we find that the pressure was slightly above the normal
until 4.30 P. M. (_A_), when the works began to raise the pressure
little by little, in order to compensate for the increased loss due to
increased flow through the mains. At 6.15 P. M. (_B_), the works ceased
increasing the pressure. While this increase lasted--from 6.15 P. M.
(_B_) to 10.15 P. M. (_C_)--our friend near the works suffered under
twenty-one tenths pressure, the gas blowing merrily through the tips
and the meter conscientiously registering gas wasted as well as gas
utilized. From 10.15 P. M. (_C_) the pressure falls by steps during the
ensuing two hours, finally reaching eleven tenths just after midnight
(_D_), which latter pressure is quite steadily maintained until the
following forenoon. The service from bedtime to dinner time should have
proved quite satisfactory. One would naturally expect to find this
consumer complaining of high bills, however.
[Illustration: EXHIBIT 3.]
Visiting the fellow at the distant end of the line, we find conditions
widely at variance from those already considered. Exhibit 2 tells a
new story. The recording gauge was placed in service at 4 P. M. (_E_),
and shortly afterward (_A_), the pressure began to fall. The jets grew
dimmer and dimmer, while the Welsbach mantles became petticoats of
red, with hems of white at the bottom. No wonder this man complains
of ‘poor’ gas, while some learned friend, dropping in for an evening
cigar, explains that there is ‘air in the pipes.’ The one consolatory
reflection is that, at all events, the poor fellow had a good light to
undress by (_B_ to _C_).
[Illustration: EXHIBIT 4.]
Exhibits 3 and 4 come from my own residence. Together they form a
‘before-taking’ and ‘after-taking’ advertisement--not of medicine,
but of a gas governor. The fact that I am located at a considerable
distance--several miles--from the works, and am supplied through a main
laid a number of years ago, when the territory was sparsely settled,
enables me to present Exhibit 3. Comment on this record is unnecessary.
After securing this diagram I installed a governor and set it at eleven
tenths. Exhibit 4 shows what happened. I am now doing for myself, and
at my own expense, that which the gas company fails to do for me. This
governor, therefore, renders me almost entirely independent of the
gas company; and, in order to demonstrate more clearly to what degree
this independence extends, the gauge has been allowed to run for
forty-eight hours without changing the card, thus super-imposing the
record of the second day upon that of the first. Note how closely the
readings for the two days agree. The governor is a protection against
excess of pressure only; if the street pressure falls below eleven
tenths--the point at which my governor is set--automatic regulation
ceases, and my gas simply becomes subject to practically the same
variations as exist on the main. Happily, the latter condition is
infrequently realized in our neighborhood. No argument is needed to
prove how successfully a governing device of this nature can cope with
the trouble indicated by Exhibit 1, or how utterly inadequate it is to
afford relief from the evil depicted in Exhibit 2. Increased pressure
is the only remedy for the latter.
The gas company does not recommend the use of these house-to-house
governors--presumably because such a recommendation would be in effect
an admission that the service as now maintained by the company is not
satisfactory. Indeed, the less enlightened officials--and it is these,
unfortunately, with whom the consumer has generally to deal--positively
and unreasoningly condemn all such regulating devices. In spite of
this, there exist to-day several gas-reduction companies, whose sole
occupation consists in exploiting various gas-pressure-regulating
appliances, which are rented to consumers for a certain percentage of
the monthly saving in the gas bills which their use effects.
It would appear to be a self-evident proposition that when one pays for
gas delivered at his meter he is entitled to receive that gas under
such a pressure as will afford the most satisfactory service. This
pressure is found to be one inch. Making due allowance for reasonable
fluctuations of a few tenths above the normal, any further departure
from the standard may be taken as a sure indication of a disinclination
on the part of the company to meet the expense of new pipes and
regulating apparatus. The time is not far distant when the public
will demand, not cheaper gas nor better gas, but a more satisfactory
service. But before condemning the gas company one must look to his
house piping. The company’s responsibility ends just inside the meter,
and from that point the consumer must provide satisfactory appliances,
giving the same attention to the gas pipes as he gives to the plumbing.
This is seldom done and the company is frequently blamed for the
neglect of the householder.
The gas engineer, steering between the Scylla of ‘poor’ gas and the
Charybdis of excessive pressures, finds himself still ‘dangerous in the
rapids’ of financial expenditure. At present he is doing the best he
can with the money doled out to him by the management.
It will be observed that up to the present point the gas meter itself
has played no part in the discussion. The meter, although greatly
maligned, is in reality an eminently satisfactory piece of mechanism.
Concerning this apparatus many erroneous notions prevail. One of these
is that a householder may burn thousands of feet of gas without cost
to himself, provided he keeps the company in blissful ignorance of
the employment of gas for heating purposes upon his premises. The
demonstration of the falsity of this idea lies within the reach of any
one who will take the trouble to read his own meter on those days on
which the company’s indexer pays his monthly visits.
[Illustration: FIG. 1.--READS 3,300 CUBIC FEET.]
[Illustration:
FIG. 2.--READS 19,800 CUBIC FEET. The apparent reading is 29,800.
The gearing of the indexing mechanism is not especially delicate,
and it frequently happens that the dial of one denomination begins
to record before the hand of the next lower denomination has made a
complete revolution.
]
[Illustration: FIG. 3.--READS 19,800 CUBIC FEET.]
Figs. 1, 2 and 3 represent different states of the index usually
employed on the three, five and ten light meters, the sizes commonly
found in our dwellings. The smaller dial, placed centrally above the
other, is known as the ‘proving dial,’ and, being used merely for
testing purposes, is not considered in reading the gas consumption.
Although the index dials vary in nomenclature as well as in number,
it is generally safe to consider that if the name is placed _above_
the dial a complete revolution of the pointer is required to register
the amount of gas indicated by the name; whereas if the name is placed
_below_ the dial each numbered division of the dial represents the
amount corresponding to the name. If doubt still exists as to the value
of each division of the lowest or right-hand dial, remember that no
meter index is designed to read less than one hundred cubic feet for
each division of the circle.
After one has indexed his own meter for a month or two he is in a
position to begin checking the bills presented. The ‘present state of
meter’ and the ‘previous state of meter’ are always specified, and the
mere subtraction of the former from the latter gives the consumption.
This is not invariably the case, however. After a meter has registered
its maximum reading--100,000 in the smaller sizes--it passes over
the zero point and begins to build up a new record. This happens at
intervals as long as the apparatus is kept in service. Before me lies
a bill giving the ‘present state’ as 1,700 and the ‘previous state’
as 96,300. Since the meter was continuously employed, it must have
registered up to 100,000, so that it registered 3,700 cubic feet on the
old score before recording 1,700 cubic feet on the new. Consequently,
adding 1,700 to the difference between ‘previous state’ and the highest
possible reading gives 5,400 cubic feet--the amount consumed during the
month. By reading one’s own meter the detection of any error on the
part of the indexer or of the clerical force at the gas office becomes
possible. Errors of this nature are of rare occurrence, as those
who have adopted this plan of checking gas bills will testify. The
responsibility for excessive bills is thus taken from the gas employees
and thrown entirely upon the gas-registering mechanism itself. Those
people, then, who chuckle furtively over the fact that the gas company
has not ‘caught on’ to the surreptitious use of gas ranges are either
the fortunate possessors of ‘slow’ meters or are deluding themselves as
to the amount of gas which they actually consume.
[Illustration: FIG. 4.--INTERIOR OF COMMON GAS METER.]
Fig. 4 is a photograph of the common dry meter, with the front, back,
top and left side removed. It is called a ‘dry’ meter to distinguish
it from those meters, having little vogue in this country, which
employ a liquid in place of a valve motion. The apparatus shown
consists of a case divided into three compartments by a horizontal
partition one fourth of the way down from the top, and by a vertical
partition centrally placed and extending upward from the bottom of the
casing to the horizontal partition. The upper compartment contains
the registering mechanism and a small valve chamber, the latter
corresponding to the steam chest of an engine. In each of the lower
compartments is a metal disk attached to the central partition by
well-oiled flexible leathers, each disk, leather and the partition
forming a bellows. As in a locomotive, the meter really consists of two
separate mechanisms, set to operate out of phase and avoid dead centers.
[Illustration: FIG. 5.]
[Illustration: FIG. 6.]
Considering one mechanism only, recourse may be had to a diagrammatic
representation of the action (Fig. 5). Gas entering the inlet passes
into the valve chamber. Here an ordinary D-slide-valve closes two of
the openings, leaving a third through which the gas may flow into the
bellows or inner compartment. The bellows expands, gradually filling
the outer compartment, and forcing the gas out under the valve into
the outlet pipe, as indicated by the arrows. When the bellows is fully
distended the valve shifts into the position shown in Fig. 6, admitting
the inflowing gas to the outer compartment and collapsing the bellows,
whose contents are forced into the outlet pipe by the paths traced by
the arrows.
Thus, it will be observed, the meter is a volume measurer pure and
simple, measuring cubic feet with as much deliberation as is required
to deal water out of a cask by means of a pint dipper. Its percentage
of error is the same at all pressures and under all loads within its
capacity, and it measures cubic feet of gas regardless of whether that
gas be expanded or compressed.
And so we are obliged to realize, as another fallacy is exposed, that
the meter does not spin around most energetically under the higher
pressures, cheerfully and accommodatingly serving its masters by adding
a mythical cubic foot or two to the count at each revolution.
It remains, then, to consider the error of the meter. The custom is,
in New York at least, not to set a meter that registers fast--that
registers a greater volume of gas than actually passes through it. If
it is found to be slow, however, and not more than three per cent.,
it is allowed to go out. As a result, the meter, when first placed,
always favors the consumer, sometimes to the extent of recording only
ninety-seven feet of gas for each one hundred feet actually passed.
Owing to the aging of the mechanism and the drying out of the leathers,
there exists a tendency to increase the registry for each cubic foot
passed. In this way a slow meter may become a fast meter after a period
of active service. From the meager data at my disposal, it would appear
that every meter should be called in for a thorough overhauling and
readjustment at periodic intervals of from three to five years.
Assuming that there are several million gas meters in Greater New
York alone, it is but natural to expect that out of this vast number,
in spite of any reasonable care that may have been exercised in
their adjustment originally, many will be found subsequently to be
defective--some because of mechanical injury, some through sheer old
age. Unfortunately, it is not possible as yet to obtain a convincingly
large array of figures; but in the Borough of Brooklyn, where there are
in service nearly a quarter of a million meters, and where complaints
against them have been studiously encouraged by the authorities, one
hundred and eighty-seven meters have been carefully tested. Here are
the results:
21 correct
{ 3 more than 10 per cent.
114 fast, average 3 per cent { 42 between 3 and 10 per cent.
(recording 103 cubic feet for { 69 less than 3 per cent.
each 100 cubic feet actually { ---
passed) { 114
{ 0 more than 10 per cent.
52 slow, average 2¼ per cent { 13 between 3 and 10 per cent.
(recording 97¾ cubic feet { 39 less than 3 per cent.
for each 100 cubic feet { ---
actually passed) { 52
---
187
When one remembers that these one hundred and eighty-seven meters are
presumably the worst of their kind, having been put in evidence by a
naturally suspicious public, it is but fair to assume that the figures
overrate rather than underestimate the errors of the average gas meter.
Quoting from _The Progressive Age_, a journal devoted largely to the
interests of the gas industry: “The meters made to-day will remain
a long while in service before they begin to register incorrectly,
and when we consider the dampness, extremes of temperature and hard
usage they receive as they are transferred from cellar to attic, from
among the dust, cobwebs and litter of a basement closet to the corner
shelf of some coal cellar, to be the playground of rats, spiders and
cockroaches, to be drenched in summer by sweating or leaky water pipes
and wear a venerable beard of icicles in winter--to be, in fact, the
worst-used machine about a gas plant--we can not fail but express
surprise that it registers at all correctly.”
THE SUN’S DESTINATION.
BY PROFESSOR HAROLD JACOBY,
COLUMBIA UNIVERSITY.
Three generations of men have come and gone since the Marquis de
Laplace stood before the Academy of France and gave his demonstration
of the permanent stability of our solar system. There was one
significant fault in Newton’s superbly simple conception of an eternal
law governing the world in which we live. The labors of mathematicians
following him had shown that the planets must trace out paths in space
whose form could be determined in advance with unerring certainty
by the aid of Newton’s law of gravitation. But they proved just as
conclusively that these planetary orbits, as they are called, could not
maintain indefinitely the same shapes or positions. Slow indeed might
be the changes they were destined to undergo; slow, but sure, with that
sureness belonging to celestial science alone. And so men asked: Has
this magnificent solar system been built upon a scale so grand, been
put in operation subject to a law sublime in its very simplicity, only
to change and change until at length it shall lose every semblance of
its former self, and end perhaps in chaos or extinction?
Laplace was able to answer confidently: No. Nor was his answer couched
in the enthusiastic language of unbalanced theorists who work by the
aid of imagination alone. Based upon the irrefragable logic of correct
mathematical reasoning, and clad in the sober garb of mathematical
formulæ, his results carried conviction to men of science the world
over. So was it demonstrated that changes in our solar system are
surely at work, and shall continue for nearly countless ages; yet just
as surely will they be reversed at last, and the system will tend to
return again to its original form and condition. The objection that
the Newtonian law meant ultimate dissolution of the world was thus
destroyed by Laplace. From that day forward, the law of gravitation has
been accepted as holding sway over all phenomena visible within our
planetary world.
The intricacies of our own solar system being thus illumined, the
restless activity of the human intellect was stimulated to search
beyond for new problems and new mysteries. Even more fascinating than
the movements of our sun and planets are all those questions that
relate to the clustered stellar congeries hanging suspended within
the deep blue vault of night. Does the same law of gravitation cast
its magic spell over that hazy cloud of Pleiads, binding them, like
ourselves, with bonds indissoluble? Who shall answer, yes or no? We can
only say that astronomers have as yet but stepped upon the threshold of
the universe, and fixed the telescope’s great eye upon that which is
within.