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" Heretofore carrying pulleys filled with wood, hemp and India rubber in one mass, filling the groove and vulcanized in place, have been tried, but were unsatisfactory.” Babbitted pulleys are too expensive. On the Olive street line in St. Louis, there are a few experimental rubber pulleys, which have been in constant service eighty-nine days, and apparently are good for as many more days. Should this experiment prove successful, as to the durability of the rubber, these pulleys will have several advantages : They are light, weighing only 20 lbs., noiseless, easily renewed, comparatively cheap and will not injure the cable. We believe that the general practice of using Babbitt metal for the bearings of these pulleys is the best.
In roads having many curves, the curve pulleys are items of considerable expense and trouble. The function of these pulleys is to hold the cable in the proper curve. As first introduced, these pulleys not only held the rope out into the curve, but had flanges cast on them for the purpose of holding the rope up to the proper height. The best practice is to leave the flange off, and place carrying pulleys between them to hold the rope up. The flange undoubtedly wears the cable very severely. These curve pulleys should be as light and large in diameter as possible, consistent with strength and the sharpness of curvature ; they should be well balanced and perfectly true ; easy of access for oiling and readily renewed. They are generally made with a chilled face where the rope strikes. There have been a few experimental ones made with hard wood packing, which are proving quite satisfactory.
At the termini of the road the cable should be carried around a sheave of as large a diameter as consistent with distances between tracks, and never less than 100 times the diameter of the cable. Where the loop is used auxiliary cables will be found more economical.
The distinguishing features of the cable system are the cable and the grip.
All the other mechanical and engineering devices are accessory. Not only are these two members expensive as to first cost, but conspicuously so as to renewals. Other members of the system may be indifferent as to quality and workmanship, but these two must be as perfect and suitable as money and skill can make them,
At present there are three distinct methods of making cables :
First—The usual and oldest is to twist or lay the wires of the strands to the left hand, and the strands forming the rope to the right hand, or in opposite directions.
Second— That known as the “ Lang lay,” formed by the wires forming the strands and the strands constituting the rope being laid in the same, instead of opposite directions.
Third—That known as the “ Lock coil rope," composed of specially shaped wires, so formed that when closed together they interlock, presenting a uniform wearing surface, and in which each wire is firmly locked in its proper position.
The ropes now used for street-railway service are made exclusively by the first, or old method, and necessarily so on account of splicing. With our present system of splicing, ropes made by the second method cannot be safely used, and ropes by the last method cannot be used at all.
While the adoption of the later improvements in ropes may not be among the conditions necessary to the financial success of the cable system, it might save a "mint of money,” many vexatious delays, serious accidents and the recording angel trouble, It is stated on the authority of those who have had experience with the later ropes that they give a much better service than the old style.
It is hoped that in the near future electric welding may be applied successfully to the splicing of cables and that these improvements can be utilized to reduce the heavy expense due to the rapid failure of cables.
Grips. As to the two classes of grips in use there is probably little difference in the wear of the cable. The bottom and side grips can be made equally efficient. On roads having many crossings, the bottom grip requires the least expenditure of money.
The grips should be so designed that the wearing parts can be renewed with the least possible waste of material and labor. The material should be of good quality and as perfectly fitted up as possible. It is an expensive mistake to construct grips of high-priced materials and have them thrown together in an unskillful manner. Rather use low price material of sufficient strength and put the money into the workmanship.
The cable and grips should be inspected thoroughly once in twenty-four hours, for upon the proper working of these depend the freedom from blockades and accidents, the consequent annoyance to the public, and the final success of the road.
The practice of using long solid dies is preferable to that of using roller dies. Any device in a grip which makes contraflexure in the rope is to be avoided.
The practice of many grip men of applying more power to the grip after the load has been completely started, is not only injurious but also a great source of expense in grip repairs.
CONDUIT. The permanent way and conduit should be so constructed as not to interfere with the free and perfect operation of the mechanical appliances. To this end it is necessary to have the conduit large enough to admit of a reasonable amount of street refuse being retained without cleaning, as frequent cleaning of the conduit is expensive.
Conduits that require cleaning but once or twice a year are preferable. This, however, depends somewhat upon the character of the street and amount of traffic. The expensive points in this respect will be found at cross streets, at cable and horse car crossings, at valleys and in the various wheel pits. The drainage should be ample enough to carry off the water of the heaviest rainfall.
The slot opening should be as wide as city ordinances and public safety will permit—as usually made three-quarters of an inch or more. The slot rails
should be made adjustable on the yokes, to the extent of at least once and a half the width of the opening. These rails, of whatever pattern, should be strong, straight and properly lined.
Of the many devices for preventing the slot closing in extremely cold and changeable weather, there are none perfect and none that have not allowed the slot rails to move more or less at times. The space between the slot rails and the track rails should be well paved, rammed and fitted, so that accumulation of water will be prevented. Freezing of water in the interstices of the paving in this space is the frequent cause of slot closure.
Other conditions and elements entering into the cable system and affecting it financially, such as equipment, car houses, machine shops, accident signal service, methods for handling old and new cables, and running trains by time cards, methods of preventing blockades on account of fires, snow, etc., cover so large a field and are of so much interest and importance that any treatment of them in this report would be necessarily so brief that it would be valueless and tire
Finally, your Committee begs the indulgence of the Association, and trusts that a sufficient number of points have been touched upon to draw out a discussion that will develop some definite and valuable knowledge concerning the conditions necessary to the financial success of the cable power.
DISCUSSION ENSUING ON THE CABLE POWER.
The President: This whole question is now open for discussion, or any other action that you may be pleased to take.
Mr. Wm. Richardson: I would move you, sir, that the President of the Association, who from his long and full experience on this question must be able to instruct any and all of us, be requested to speak first on this report.
The' motion was seconded by Mr. Frayser.
The Secretary put the question that the President, Mr. Holmes, be requested to make the first statement on the subject of cable motive power. Unanimously carried.
The President called Vice-President Frayser to the Chair.
REMARKS OF PRESIDENT CHARLES B. HOLMES ON THE
The President, Mr. Charles B. Holmes, of Chicago : Mr. President, please shut me off when the time comes, for this subject is so large and it involves so much ; it touches so nearly the
powers which must come to help us out in this work, that when I get started there is no saying how far I will go. The report submitted this morning is a full and exhaustive one; one that is full of exceedingly interesting matter, especially to those who have had any experience in the building and operation of cable lines. One of the most important suggestions made in
is the matter of engines. You take an dinary engine, one of the old-fashioned valve engines, and it is of very little worth
a cable line. The fluctuations of power and strain come so quickly, that we need an engine for that purpose which will operate as quickly as the fash of the eye, and something that will be true in its operation and control the power, so that when a strain comes quickly one way, and there is a corresponding relaxation the other, the engine will respond at once to the work which it has to do. In connection with the question of the engine comes the matter of the boiler. It requires a much larger amount of boiler capacity, than of engine power, for the successful operation of a cable line. Mention was made of the cable or haulage rope. So far as I know, all cable lines in this country are now operated with a six-strand rope made of sixteen wires to the strand, sometimes with nineteen wires to the strand. From our experience in Chicago, having operated a cable line since 1882, we have settled down on a sixteen-wire strand, the outer wires of the strand being larger than the inner, so as to take the abrasion of the grips, without wearing away too rapidly. The inner portion of the rope has a hemp center, so that the strands fit down into the hemp center, and thus do not grind on each other. As we all know, there is a great deal of elasticity in a new wire rope. I have heard it stated by a gentleman who is a wire rope manufacturer, that a wire rope four thousand feet long will stretch two hundred feet. I know that there is a great deal of elasticity to a wire rope when it is first put in and commences its operation. It will stretch within two weeks to a distance of a hundred feet, and for the next two or three weeks it will stretch perhaps thirty, fifty or sixty feet more. This is all provided for by the winding of the slack on the drum and tension carriage, which is a device operating back and forth to keep the tension correct. In 1881 the Chicago City Railway Company operated two hundred and sixty-three cars and carried nineteen millions of people. This present year, 1888, we are operating one thousand cars and carrying fifty-seven millions of people. I know of nothing in the history of the world which has shown a development of street-railway interest equal to that ; from two hundred and sixty-three cars to one thousand cars in the short space of seven years ; and we do not put on the cars just for fun and run them empty either.
The transmission of power from the engine to the drums, which move the cables, has been alluded to in the report, and reference has been made to cotton ropes. There may be more than one, but I know of only one place where cotton ropes are used for this purpose, and that on the Geary Street line, in San Francisco. It is a beautiful thing; as noiseless as the working of a watch ; but I fear that for the heavy work which we have to do in Chicago, the cotton ropes would fail us in the transmission of power. The strains on the cables come so quickly and with such power, that these cotton ropes, not being equal in their tension, would sag more than usual between the drums, and would not be equal to carrying the load; and consequently the ropes would be stretched more in some cases than in others, and there would be more slipping than there ought to be, so that my own faith in cotton ropes for a large plant is weak. We have operated during this Summer as high as two hundred and sixty-three trains at a time, some three cars, and others four cars; and the amount of power which is necessary to move this vast number of trains loaded with people is enormous; for the extensions which we have made to our lines enable us to carry the people from all portions of the division of the city in which our lines are operated out to the park; and on Saturday and Sunday afternoons it would do your hearts good to see the thousands and thousands of the workmen of our city, who have been housed up in their workshops during the week, come out in their best dress with their families with them to go to the park. We have carried from fifty to seventyfive thousand people in a single afternoon on these pleasure trips.
Allusion has been made in the report to "the percentage of power.” In my mind there is nothing more deceptive than this percentage business. I want to get at this matter in a little different way, and, I think, one that will perhaps convey to you a trifle more tangibly an idea as to what this power is. I hold in my hand a statement taken from cards of our engines, showing