Progress of Development in Water-works Practice.*

Progress of Development in Water-works Practice.*

In reviewing the progress of development in water-works practice, it is true that since the organization of this association, the efficiency of pumps has been increased to a greater extent than for any period of fifty years preceding.

I do not mean that this association should have all the credit for this improvement, but I do mean that the engineers and superintendents of water-works for the past ten years have been asking for greater efficiency in pumps and higher mechanical skill in engines. The manner of preparing specifications for pumps, engines and boilers has been wonderfully perfected in the last decade, and in addition to this the requirement of “ efficiency tests ” by experts of known reputation before the final acceptance of the work is a step in the right direction. The great care now bestowed on the mechanical finish of our highest type of pumps is giving us the best results possible under the steam pressure now in use ; but with an increase of steam pressure to 150 or 200 pounds per square inch (which the locomotive is now worked under) there is still a margin for better results.

The first “ lifting pump” was invented in 1825, but was limited in use until May 30, 1857, when Peter Morice was given a grant from the Lord Mayor and Commonalty of the city of London for the term of 500 years, for the supplying and conveyance of water into houses by pipes from an artificial forcer from the London bridge, on condition that the said Peter Morice should pay ten shillings annually into the chamber of London ; and he was authorized to erect an engine within the first arch of the London bridge for that purpose ; and as this device completely effected the object, another grant was given by the same authorities for the use of another arch in the bridge. A description published in 1633 says: ‘‘The present supply of good water for London is like to be very much enlarged by the great improvement of the water-works of Peter Morice, before mentioned, who being a Dutchman, in the twenty-third year of Queen Elizabeth, first gave assurance of his skill in raising the Thames water so high as should supply the upper parts of London ; for the Mayor and aldermen came down to observe the experiment, and they saw him throw water over St. Magnus steeple ; before which time no such thing was known in England as the raising of water.” 11 is throwing water over St. Magnus steeple excited the wonder, as well as gratified the curiosity, of the citizens, for fire engines had not then been invented. It was not until 1663 that the force pump was used in the construction of fire engines. Prior to this all the engineering skill of the Romans, as well as of the contrivances heretofore adopted for supplying London with water had evidently been formed upon the well-known principle that water will flow along any channel that has the slightest inclination downward, but the purpose f Morice’s machinery was to impel the water in an ascending direction, and thus supply water in places higher than the source. The success of Morice’s invention was so patent that the city authorities of London gave him an additional grant for two other arches under the London bridge ; this second grant was for 2000 years, and was finally secured by the New River Water Company.

In 1731 there appeared in the “ Philosophical Transactions ” a very minute account of the once greatly admired London Bridge water-works, by Mr. Brighton, an engineer, who carefully described them and accompanied his detail with an engraving which had proper reference for its elucidation ; but whether at that time all the works were precisely the same in form and action as those first constructed, or if any improvement had been introduced, is not stated, and it may” be right to premise that the water-wheels and machinery being fixed in strong frames of oak, they gradually rose and fell with the tides. At that time there were three water-wheels, with the respective diameters of nineteen and twenty feet and twentysix flat boards, fourteen feet long by eighteen inches wide. The pumps used had cylinders with a length of four feet nine inches, and an interior diameter of seven inches aboveand nine inches below the valve ; the cylinders of the pumps were fixed to the top of an enclosed square iron cistern, which had appropriate apertures, with valves just below the places where they were attached, these being worked by cranks, which the revolving of the water-wheel kept in constant motion whenever the tides were flowing either up or down the river. One wheel communicated motion to sixteen pumps and their cranks were arranged for four of them to work alternately, so that each set might draw its supply of water in succession. One turn of the wheel occasioned the whole of the pumps to make 114 strokes, and when the tide flowed quickly it produced six revolutions per minute ; thus the number of strokes in that short time amounted to 684, which raised 1954 hogsheads of water in one hour.

* A special paper prepared by T. W. Yardley and read at the Milwaukee Convention of the American Water-works Association, 1893.

The engraving alluded to, gives a good idea of the wheel and pumps of over 300 years ago, that revolutionized supplying water to towns and cities to elevations higher than Its source, and was the first application of piston pumps to direct pressure for the forcing of water. The principle there demonstrated of the use of non-pulsating pumps has since been developed and perfected by that eminent mechanic and hydraulic engineer, Birdsell Holly, who for many years was the mechanical engineer of the Holly Manufacturing Company.

The evolution of pumping machinery has culminated in our day by propulsion with steam. What a transformation since the London Bridge Pumping Works of 300 years ago. And now’ with all the improvements of boilers, engines and pumps, there comes the important question of “ Economy of fuel,” and in this you are all immediately interested.

For several years past the Robert W. Hunt & Co. bureau have been called upon to make “ efficiency tests ” of boilers, engines and pumps. From these I have extracted some facts showing the importance and value of intelligent use of fuel. 1 will not weary you with the entirety of these tests, nor have I permission to name the makers of the machinery, or the places where the tests were made. I will therefore confine myself to the fuel consumed per hour ; water evaporated per hour; water evaporated per pound of fuel, head and cost of fuel per ton, showing the difference in cost of fuel per month under precisely the same conditions, and also showing the difference in cost per month between intelligent firing and the opposite.

In test No. 1 the firemen were on duty six hours each during the twenty-four required for the test, therefore, one fireman was on duty twice during the three watches of eight hours each, and under this division of observation and labor the result of each fireman was carefully noted. Fireman ‘‘A “showed a saving in fuel per month of $76.45 on the first six hours over fireman “ B,” and on his second six hours he showed a saving of $70.38 per month over fireman “ C.” On test No. 2 two firemen were on duty twelve hours each, and during this time fireman “D” showed a saving of $39.96 over fireman “ E.’ In test No. 3 there were three firemen on duty, eight hours each, and fireman “G” showed a saving of $16.12 over fireman “ F,” and $41.54 per month over fireman “ H.” The following tabulated statement in detail I submit for your better information :

The great variety of fuel used throughout the country makes the cost of pumping vary in proportion to its quality, but the same fuel used intelligently will give much better results as to economy, and in these figures clearly demonstrate the value of a fireman should not be governed by a fixed rule of salary, but his compensation should be increased in proportion to his saving. As you see by the result of test No. 1, fireman “ A ” will be a cheaper man at $100 per month than either B or C at $50 per month, and fireman D shows a saving of $40 per month over fireman E, and the same result is shown by fireman G over fireman “H.” These are facts worthy of your consideration and I submit them respectfully.

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