Scientific American Supplement, No. 392, July 7, 1883

V >> Various >> Scientific American Supplement, No. 392, July 7, 1883

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Elevators have become an established institution, and in cities of any
commercial importance are regarded as a necessity, hotels, jobbing
houses, factories, and office buildings being considered as far behind
the times when not thus provided, as a city without a water supply or a
community without a "boom." The use of elevators has made it practicable
and profitable to erect buildings twice as high as were formerly thought
of. Perhaps some of the most notable examples of this are in New York
city, where such structures as the Mills building, the buildings of the
_Tribune, Evening Post_, and Western Union Telegraph Co.. tower high
above the surrounding blocks, monuments of architecture, that without
this modern invention would reflect little credit upon their designers.
It is now found less labor to go to to the fifth, sixth, or even tenth
floors of these great buildings than it was to reach the second or
third, before their use. In these days, merchants can shoot a ton of
goods to the top of their stores in less time than it would take to get
breath for the old hoist or "Yo, heave O" arrangement. Thousands of
dollars are sometimes expended on a single elevator, the cars are
miniature parlors, and the mechanism has perhaps advanced to nearly the
perfection of the modern steam engine. If then they have become such a
firmly established institution, their bearing upon the water supply of
cities is a subject to be carefully considered.

As before intimated, there are many questions involved in the use of
hydraulic elevators, that particularly concern towns supplied by direct
pumping, and perhaps other places where the supply by gravity is
somewhat limited. In a few larger cities supplied by ample reservoirs
and mains, some of the difficulties suggested are not serious. Very
little power is necessary to perform the actual work of lifting, with
either steam or hydraulic elevators, but on account of the peculiar
application of the power, and the great amount of friction to be
overcome, a very considerable power has to be provided. It has been
estimated, by good authorities, that not more than one-quarter of the
power expended in most cases is really utilized.

With all hydraulic elevators of which I have cognizance, as much water
is required to raise the empty cars as though they were loaded to
maximum capacity. Still, to be available for passenger purposes
elevators must have capacity of upward of 2,500 pounds, particularly in
hotels, where the cars are often arranged with separate compartments
underneath for baggage. In general use it is exceptional that passenger
elevators are fully loaded; on the contrary less than half a load is
ordinarily carried, and for this reason it would appear that no actual
benefit is derived from at least one-half of the water consumed. In this
connection it has occurred to me that passenger elevators could be built
at no great additional cost, with two cylinders, small and large, the
two piston rods of which could be connected so as to both operate the
same cable, either or both furnishing power, the smaller cylinder to be
used for light loads, the larger for heavy work, and the two together
for full capacity, this independent valve arrangement to be controlled
by a separate cable running through the car. Whether this plan is
practicable or not must be left to elevator manufacturers, but it seems
to me that with the Hale-Otis elevator for instance (which is conceded
to be one of the best) it could easily be accomplished. Certainly some
such arrangement would effect a great saving of water, and perhaps bring
water bills to a point that this class of consumers could afford to pay.

Hydraulic elevators where the water is used over and over again, by
being pumped from the discharge to elevated tanks, cut little or no
figure in connection with a city's water supply. When fuel, first cost,
attendance of an engineer, and the poor economy of the class of pumps
usually employed to perform this work are considered, the cost of
operating such elevators is greatly in excess of what it would be if
power were supplied direct from water mains, at any reasonable rate. The
following remarks will then relate almost exclusively to that class of
hydraulic elevators supplied with power directly from the water mains.

Let us now consider whether they are a desirable source of revenue, and
in this my knowledge does not exceed my actual experience. Few elevator
users appreciate the great quantity of water their elevators consume.
Even in Kansas City, where, on account of the high pressure carried,
much smaller cylinders than ordinarily are required, it is found that
passenger elevators frequently consume 500,000 to 800,000 gallons of
water per month, which will make a very considerable bill, at the most
liberal rates. I have, therefore, concluded that the quantity of water
was so large that, unless liberal concessions were made, it would be a
hardship to consumers to pay their water bills, and have therefore made
a special schedule, according to quantity, for elevators and motors,
these rates standing below our regular meter rates, and running to the
lowest point at which we think we can afford to furnish the water. This
schedule brings the rate below what we would receive for almost any
other legitimate use of water; and, in view of our rapidly increasing
consumption, and the probability of soon having to increase all our
facilities, it is an open question whether this will continue a
desirable source of revenue.

In Kansas City we have elevators of various manufacture: the Hale-Otis,
Ready, Smith & Beggs, O'Keefe, Kennedy, and perhaps others, each having
its peculiarities, but alike demanding large openings in the mains
for supply. These large openings are objectionable features with any
waterworks, and especially so with direct pumping. An occurrence from
this cause, about two years ago, is an experience I should not like
repeated, but is one that might occur whenever the pressure in the mains
is depended upon to throw fire streams. In this instance a large block
of buildings occupied by jobbing houses and having three elevators was
burned down, and the elevator connections broken early in the fire,
allowing the water to pour into the cellars in the volume of about
twelve ordinary fire streams. This immense quantity of water had to be
supplied from a 6-inch main, fed from only one end, which left little
pressure available for fighting the fire, and as a matter of course
failure to subdue the fire promptly was attributed to the water-works.
We have since had up hill work to restore confidence as to our ability
to throw fire streams, although we have demonstrated the fact hundreds
of times since.

From this time we have been gradually cutting down on the size of
openings for elevator supply, but under protest of the elevator agents,
who have always claimed that they should be allowed at least a 4-inch
opening in the mains, until we have found that under 80 to 90 pounds
pressure two to four 1-inch taps will answer the purpose, provided the
water pipes are of ample size.

The "water hammer" produced by the quick acting valves of elevators has
always been objectionable, both in its effect at the pumping-house
and upon water mains and connections. To obviate this, Engineer G. W.
Pearson has suggested the use of very large air chambers on the elevator
supply, and still smaller openings in the mains, his theory being that
the air chambers would not only materially decrease the concussion or
"water hammer," but that they would also act as accumulators of power
(or water under pressure) to be drawn from at each trip of the elevator,
and replaced when it was at rest. This plan I have never seen put to
actual test, but believe it to be entirely practicable, and that we will
have to ultimately adopt it.

All things considered, the plan of operating elevators from tanks in
the top of buildings, supplied by a small pipe connected with the
water-mains and arranged with a float valve to keep the tank filled, I
believe to be the best manner of supply, except for the great additional
cost of putting up such apparatus. By this arrangement the amount of
water consumed is no less, in fact it would ordinarily be more than with
a direct connection with the mains, but it has the advantage of taking
the water in the least objectionable manner. Still, if this mode of
supply were generally enforced, the large first cost, an additional
expense of operating, would undoubtedly deter many from using elevators.

Another evil in connection with the use of elevators, and which no doubt
is common, is the habit many parties have of keeping a key or wrench to
turn on and off the water at the curb. This we have sought to remedy
by embracing in our plumbers' rules the following: "All elevator
connections in addition to the curb stop for the use of the Water
Company must be provided with another valve where the pipe first enters
the building for the use of occupants of the building." Without this
extra valve it was found almost impossible to keep parties from using
the curb valve. In most cases the persons were perfectly responsible,
and as there was no intent to defraud the company by the act, they would
claim this privilege as a precaution against the pipes bursting or
freezing. This practice was very generally carried on, and was the
direct cause in at least two cases of very serious damage. In the
instances referred to, the pipes burst between the elevator and the
area wall of buildings, and the valves outside had become so worn
from frequent use that they would not operate, allowing the water to
literally deluge the basements before the water main could be turned
off.

One of the greatest causes of waste from elevators is the wearing out of
the piston packing, this being particularly troublesome in most of the
Western cities, where the water supplied is to a large extent from
turbid streams, carrying more or less fine sand or "grit," which cuts
out the packing of the pistons very rapidly. The only practicable remedy
for this is close inspection, to see that the pistons do not allow water
to pass, a fact that can readily be determined from the noise made in
the cylinder when the elevator is in motion going upward.

I have reserved one of the most annoying features of elevator supply for
the last, hoping to work myself into a mood to do the subject justice,
but doubt if it can be done in language proper to use before this
dignified body. I remember on one occasion the mayor of our city, in
discussing a job of plumbing, said that it seemed to him "that even a
plumber ought to know something about plumbing." Now it would seem that
even elevator agents ought to know something about elevators, but from
the following incident, which is but one of many, I am led to believe
that they are not infallible to say the least. Only a short time since,
one of these very reliable (?) agents reported at our office that he had
just attached a new indicator to the elevator of a leading hotel. He was
asked: "What does it register?" and promptly replied, "Cubic feet."
In this case our inspector had already made an examination, and had
correctly reported as follows: "Hale elevator; indicator started at zero
February 28; internal diameter of cylinder, 12 inches; travel of piston
for complete trip 301/4 feet; indicator registers for complete trip, 4."

When it is understood that we had for a long time been assuming that
elevator agents knew about all there was to know on the subject, a
comparison of statements of this agent and our inspector is somewhat
startling. Now let us see what the difference amounted to: At the end of
the month the indicator had registered 12,994; calling it cubic feet,
this register would equal 97,195 gallons. According to our inspector,
this same register would equal 578,233 gallons, or a difference of
nearly half a million of gallons for a single month. Our experience with
the agents in Kansas City has shown that they will, if allowed, put any
kind of an indicator on the most convenient point of any sort of an
elevator, without the slightest regard as to what it was intended to
indicate; then report it as registering cubic or lineal feet, whichever
they find the indicator marked. On the same principle they could as
well change the fulcrum of a Fairbanks scale, and then claim it weighed
pounds correctly, because pounds were marked upon the bar. We have
lately prepared a blank, upon which these agents are required to make a
detailed report upon the completion of an elevator before the water
will be turned on, which it is hoped will to some extent correct this
trouble.

I have come to regard an elevator indicator with a feeling of wonder.
Some years ago, when the "planchette" first came out, I remember that
it acquired quite a reputation as a particularly erratic piece of
mechanism, but for real mystery and _innate cussedness_, on general
principles, commend me to the indicator. Why, I have known an indicator
after registering a nice water bill, to deliberately and without
provocation commence taking it all off again, by going backward. This
crab-like maneuver the agent readily explained by saying the "ratchet
had turned over," but even he was unable to show us how to make the
bills after these peculiar gyrations. I also find that it is quite a
favorite amusement for indicators to stop entirely, like a balky horse,
after which no amount of persuasion will bring them to a realizing sense
of their duty.

Even at the best, these indicators are very apt to get out of order,
necessitating greater watchfulness in supplying elevators than for any
other purpose for which water is furnished.

Accidents in connection with the use of elevators are common throughout
the country, and in Kansas City had, until within a short time, become
of altogether too frequent occurrence. The great cause of this I believe
to be due to the fact that the parties who usually operate elevators
are the very ones who know least about them; the corrosion of pistons,
crystallization and oxidation of cables, and many other disorders common
to elevators, being matters they do not comprehend. The frequency
and fatality of these accidents in Kansas City finally led the city
authorities to appoint an Elevator Inspector, who is under heavy bond,
and whose duty is to examine every elevator at least once a month, and
to grant license to run only such as he deems in safe condition. Thus
far since the establishment of this office we have had no serious
accidents, which leads me to the belief that in most cases a monthly
examination will discover in time the causes of many terrible
casualties; also that it is not safe to operate elevators unless so
inspected by some competent person.

The hatchways of elevators in large buildings are points greatly feared
by firemen. They well know that when a fire once reaches this shaft, it
takes but a moment for it to be carried from floor to floor, until the
building is soon past saving. Although this great danger is well known,
it is the exception rather than the rule to provide elevators with
fire-proof hatches. A properly constructed elevator should, it seems
to me, be provided with hatches, or better still, built within brick
fire-proof walls, with openings to be kept closed when not in use. In
this way costly buildings, valuable merchandise, and many lives would be
saved from fire every year.

Although considerable has been said on the subject of elevators, I am
aware that the ground has not been covered, and that difficulties have
been pointed out more than remedies suggested. There is much yet to be
brought out by the engineers, to whom the subject more properly belongs.

In the mean time, although elevators claim many of the objectionable
features in the business of water supply, most of them are not of a
nature that should condemn their use; on the contrary, I hope that
with the joining of our experience there will be an improvement in the
methods of their supply. Inasmuch as they must be furnished with water,
all that can be done is to adopt such rules and fix such rates as will
compensate in some degree for their objectionable qualities.

WATER MOTORS.

My remarks on this subject I trust will be more to the have been point
than they upon the questions already discussed. Certainly my ideas are
more decided, so far at least as supplying water motors is concerned.

In many respects I believe water motors furnish as nearly perfect power
as it is possible to attain. A motor, for instance, properly connected
and supplied by the even pressure from a reservoir is probably the most
reliable and steady power known, not excepting the most improved and
costly steam engines. The convenience and little attendance necessary in
operating make them especially desirable for many purposes. Where only
small power is required, or even where considerable power for only
occasional use is desired, they are particularly well adapted, and
can be driven at small expense. Even for greater power they possess
advantages over steam engines which, to a considerable extent,
compensate for the large water rates that ought to be paid for their
supply. These advantages are in the first cost of a motor, as compared
with a steam engine, the saving in attendance and fuel, the convenience
and cleanliness, and in some cases a saving in insurance by reason of
their being no fire risks attendant upon its use. At just what point
steam becomes preferable, however, is a question depending considerably
upon water rates, but to some extent on other circumstances, leaving
it largely a question of judgment. As with elevators, there are
difficulties involved in their supply that unless carefully guarded make
water motors anything but a desirable source of revenue. How often is
the argument advanced: "Why, I only use water for a quarter of an inch
jet!" Showing how little people who use motors or elevators or fountains
realize the quantity of water they consume. This class of consumers may
be placed on one footing, to wit, a class who, in spite of the fact that
they are supplied with water for much less than any other, feel that
they are imposed upon, and cannot be made to think otherwise.

Though not as large as for elevator supply, water motors require liberal
openings in the mains, and frequently the fault of having too small
supply pipes is sought to be remedied by openings in the water mains
much larger than needful. A table prepared by an engineer who had given
the matter study, or by some motor manufacturer, showing the size of
taps, or openings, for the proper supply of motors, with the various
jets, under different pressures, would be of general use to water-works
people. In order to use water to the best advantage, the full pressure
in the main, so far as practicable, should be had at the jet, but in
order to accomplish this it is not necessary to use as large taps as are
ordinarily demanded, but to provide supply pipes of sufficient capacity
to deliver the water to the point of discharge with the least possible
friction. Lately this theory has been put in practice to some extent by
us, and the result has shown that in this manner we are able to supply
motors through smaller taps than beforehand with as satisfactory
results.

It is a general practice throughout the country to make annual or
monthly rates for water motors, and from my observation I believe I can
safely venture the assertion that in three-quarters of the cases the
rates charged will not equal 50 per cent. of the lowest meter rates in
force in these places. Although the Kansas City Water-Works has not
perhaps been generally accorded the reputation of being the most liberal
"monopoly" in the country, still I have had occasion at times to make
some such claims as an inducement to its generous support. But with all
its liberality, I am free to say that we cannot begin to meet the rates
for motors that parties claim to have paid almost everywhere else.

The St. Louis Water-Works, where the rates are substantially the same as
in Kansas City, have been quoted as having the following motor rates,
but whether correct or not my inquiries have failed to determine:

"On the supposition that motors are to be used ten hours per day for 300
days per year, motors are assessed for--

___________________________________
1/4 inch jets | $120 per annum. |
3/8 " | 198 " " |
1/2 " | 300 " " |
----------------+-----------------+

These rates based upon a charge of 50 cents per 1,000 gallons."

From Col. Flad's Report as Engineer of Public Works, May 1, 1876, p.70,
it is found that with 42 pounds pressure a 1/2 inch orifice will discharge
2,160 gallons per hour, 21,600 gallons in 10 hours, or 6,480,000 gallons
in 300 days, which at 20 cents per 1,000 gallons would amount to $1,296,
for which they assess the rate $300. From all of which I would conclude
that there must be a lack of harmony somewhere between the engineering
and office departments.

I have made some estimates myself for water motors, basing rates upon
the number of hours it was claimed the motors would be in use, and
afterward supplied the same motors by meter measurement; in every case
found that at least twice as much water was used as had been estimated.
Although estimates were carefully made upon what was believed to be
a reliable basis, these repeated similar results have led me to the
conclusion that the only way to supply motors is to make it an object to
the users of them to be economical. In other words, I believe the way to
supply water motors is upon an estimate that they will run 24 hours per
day and 365 days per year, or, more properly still, supply them only by
meter measurement. At all events this is henceforth my policy; or, in
other words, "on this rock I stand," believing it the only equitable way
out of this difficulty.

That class of motors or water engines operated by water pressure in
close cylinders upon pistons as with steam in a steam engine, I believe
could be easily supplied by measurement of water without a meter. This
could be accomplished by the use of "revolution counters" or indicators,
as the amount of water required per revolution could be readily
determined, and when once computed the cylinders would measure out the
water as accurately as a meter. The only objection to this plan is the
expense of counters, which is considerable; and as to indicators, it may
have been observed that I have little faith in their reliability. With
cheap revolution this class of motors would be free from many of the
objections raised in regard to motors generally.

The practical conclusion that I would draw from a consideration of
this subject is that the question of whether the supply of hydraulic
elevators and motors is desirable in its effects upon the water supply
is one that hinges so delicately upon their being carefully governed,
connected, and restricted, that while on the one hand they may be made
the source of large profit, and at the same time a public benefit, on
the other hand, unless all the details of their supply be carefully
guarded by the wisest rules and greatest watchfulness, their capacities
for waste are so great and the rates charged necessarily so low, that
they may become the greatest source of loss with which we have to
contend. I therefore trust that this discussion will be continued until
an interest is felt that will result in our all receiving much useful
information upon two most important factors of our business.

As this paper has been long for the information contained, I will close
with the earnest wish that it may at least be of service in bringing
these important but often neglected subjects to the attention of the
thinking and intelligent body of men, of whom many have had much longer
and more general experience in relation to these matters, and whose
views when expressed will consequently be of more interest and have
greater weight. Thus as a result may we all derive the benefit of
whatever useful information there is to be gained by this annual
interchange of experiences in the all-important business of public water
supply.

* * * * *

WATER SUPPLY OF SMALL TOWNS.

We now describe the new waterworks lately erected for supplying the town
of Cougleton, Cheshire. The population is about 12,000, and the place is
a seat of the silk manufacture. After various expensive plans had been
suggested, in the year 1879 a complete scheme for the supply of the town
with water was devised by the then borough surveyor, Mr. Wm. Blackshaw,
now borough surveyor of Stafford. These we now illustrate above by a
general drawing, and a separate drawing of the tower. With respect
to the mechanical arrangements, the Corporation called in Mr. W. H.
Thornbery, of Birmingham, consulting engineer, to decide on the best
design of those submitted, and this, with modifications made by him, was
carried out under his inspection. The water, for the supply by pumping,
is obtained from springs situated at the foot of Crossledge Hill, about
a mile from the town. It does not at present require filtering, but
space enough has been allowed for the construction of duplicate
filtering beds without in any way interfering with the present
appliances. These filter beds are shown in our perspective illustration,
but they are not yet built or required.

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