Popular Science Monthly/Volume 71/July 1907/Notes on the Development of Telephone Service VIII



X. Early Aerial Telephone Cables

PROBABLY John I. Sabin was the first telephone man to use an aerial cable. In connecting his line in San Francisco in 1879, he did not run his circuits into a cupola, as was then the fashion, but employed several lengths of a special cable made by Eugene F. Phillips, of Providence. This cable was composed of forty No. 20 soft drawn copper wires, double braided with cotton, then double wrapped in reverse order with rubber paper, the whole being wound with a cotton or jute covering. It cost 20 cents a foot at the factory. It was suspended by using long canvas slings about two feet apart and attached to two heavy iron wires.

In referring to the growth in overhead circuits, Mr. Phillips stated that:

The natural increase in the number of aerial wires created a demand for better insulation and grouping in cables. Hundreds of miles of No. 12 iron wire were braided and dipped in suitable compound for this use. The annoyance from induction soon made a call for anti-induction cable. This want was supplied by a tin-foil cable so called, in which each conductor, after being insulated, was enclosed in a strip of this tin-foil. Cotton-covered wires to the extent of 50 or 100 were cabled together, and after being saturated with paraffine were placed in a lead pipe. This style of aerial cable, although quite satisfactory, has to a great extent been replaced by the paper-insulation underground cable of the present day.

Aerial cables were in use in New York City late in 1879, and before the close of 1880 a total of over 75,000 feet was in use in the city and on the Brooklyn Bridge, principally of ten-conductor capacity. In September, 1880, C. E. Chinnock told the delegates to the first telephone convention:

We have over the East River bridge at the present time, four cables, 3,800 feet long, each cable with seven conductors. These cables have taken the place of cables that were previously there with the ordinary kerite and gutta-percha insulation. In using the cables and talking on one wire, you could hear whatever was said on another wire, and by wrapping each conductor with lead and grounding at intervals, all of the escape and all induction were completely eliminated. These cables have been in use, two of them for six months, and one for nine months, and are now working perfectly.

In May, 1880, W. D. Sargent used a lead-covered aerial cable to connect two exchanges in Philadelphia. This cable was made by David Brooks, Jr., son of the inventor of the Brooks cable. It was composed of 42 twisted pairs of No. 18 cotton-covered wires, which were wrapped together and drawn into a lead pipe one inch in diameter. Then a mixture of melted paraffine and rosin was poured into the pipe, the whole forming a solid mass on cooling. This cable was about 600 feet in length and was suspended from three heavy iron wires by loops made of No. 14 iron wire.

At one of the telephone conventions C. N. Fay stated that

the use of cables for telephone purposes in Chicago began in 1879, when a 50-wire Brooks oil-pipe cable, 925 feet long, was placed in the Washington Street tunnel under the bed of the Chicago River. The conductors were made of No. 20 copper wire, insulated with cotton, and drawn through an iron gas-pipe previously polished smooth on the inside. The ends of the pipe were elevated, and upon each end was placed a reservoir capable of holding three or four gallons of paraffine oil. After the pipe was put in place, the cable was drawn through. Paraffine oil was then poured into the reservoirs until the pipe was filled from end to end and both reservoirs were full, when the caps were screwed on and the whole made tight. There was a loss of oil from evaporation and leakage through the pipe, requiring a refilling about once in six months. In 1880, a 75-pair cable of similar construction, 450 feet long, was placed in the LaSalle Street tunnel under the Chicago River; another one being placed in the spring of 1881. In 1884, all the oil-pipe cables were in good and satisfactory working condition. . . . . The first aerial cable was put up in Chicago in September, 1882, and was a 50-pair Patterson cable 1,350 feet long.

Six Brooks oil-pipe cables were in use early in 1880 in Milwaukee. Each cable was about five hundred feet in length and composed of fifty single conductors, and all were considered "very satisfactory."

It is of historical interest to note that in April, 1843, S. F. B. Morse detailed to the Secretary of the Treasury the specifications under which forty miles of a four-conductor lead-covered cable would be made. Each wire was to be

once covered with cotton thread, to receive two coatings of shellac varnish; then wound with a different colored twine to designate, in case of necessity, any particular wire in any part of the course. The four lengths are then laid side by side and bound together in a single cord by another winding of cotton twine. The conductors thus prepared are ready to be introduced into the lead pipe.

XI. Forcing Telephone Wires Underground

When the underground question first came up, the leading telephone companies made it clear to the authorities of the respective municipalities, that any hesitancy in removing overhead wires and placing them underground was not due to an unwillingness to make the additional and very large investment necessary, but to contending with obstacles that then appeared insurmountable. There was no practical underground system suitable for telephone distribution in American cities. Several experimental systems were being promoted, but all appeared to possess little practical value. One promoter laid a half-mile of his pipe underground and then invited a large number of telephone, telegraph and electric-light men to thoroughly inspect the condition of pipes and wires. Following this inspection came a banquet of nine courses, at which eight different wines were served to more than a hundred guests. Referring to proposed drastic legislative action to force the wires underground, David Brooks wrote on March 13, 1882:

I have every reason to believe that the great quantity of poles and wires that are now so objectionable in our streets may be dispensed with in the future, and while the company is so earnestly engaged in testing this problem of underground wires, I can see no good result to be obtained by the passage of these bills. It will be to their interest to make an underground system whenever it is practicable.

The attitude of the parent Bell company on the underground question is shown in President Forbes' annual report dated March 18, 1882, in which he states that

our experiments in underground cables, while not as successful as we had hoped, have given sufficient promise of satisfactory results to warrant us in undertaking at considerable expense to test the different methods. With this object, we have asked permission to put down cables in Boston, and, as soon as the needed consent is obtained, we propose to make careful and thorough practical tests of the best systems offered. . . . The cost of replacing an extensive overhead system in a large city is so serious that it can not be hastily decided upon; yet, if the wires can be laid underground and made to work rightly, at a cost which will not be prohibitory, it is hoped that the service will be better than now, and the cost of operating less than by overhead wires.

The first Morse telegraph patent of June 20, 1840, refers to the wires being laid underground, and a portion of his first telegraph line was buried, but proved inoperative, while on a section built with the aid of cattle-horns used to support the line on and insulate it from a stone viaduct, good service was secured. But the first American patent for underground lines was issued in 1869, and it was the only one issued until 1873, when two more were issued. A total of twenty-one patents were issued prior to 1880, when, in that year, seventeen were issued, and twenty-eight in 1881. Aerial as well as underground conduits, evidently based on the old Graves method of 1858, or the Carter of 1875, were also suggested as a remedy for the multiplicity of overhead, wires, and elaborate systems supported upon iron posts or columns erected either on one side of a street or overarching the roadway and supporting the wires in the center were made, upon paper, to appear very attractive, and earnestly advocated as a practical public improvement. In fact, the opinion was expressed at the third telephone convention held at Saratoga Springs, that

with a light and ornamental aerial cable support the requirements of the public could be satisfied and the introduction of subterranean wires obviated entirely or confined wholly to important trunk routes. ... The Scott elevated wire-way system consists of cupolas located upon housetops, separated at any convenient distance and connected by a suitable tube, through which wires to the number of two or three hundred are drawn and properly connected at the cupolas. The tube is preferably made of rubber and braided fabric upon a spiral foundation of wire, by which the tube retains its circular form. The tube is suspended from a supporting wire of sufficient strength to stand the strain of severe wind and the weight of accumulated ice and snow. The wires, which may be either well insulated or even the ordinary braided or double-wound wire, can be drawn in singly or in groups and connections made at the cupolas. The tube, being impervious to moisture, the channel inside will remain perfectly dry. Since the last report of the committee, it has been introduced on a limited scale in the city of Boston and it will soon be extended.

While no underground system satisfactory to telephone men was available in 1880-3, a few wires had been laid underground and some experience of an expensive character gained. For instance, the Western Union carried out some costly experiments with underground wires in New York City during the four years, 1876-80. In 1876, two 4-inch iron pipes were laid from the main office to Pier 18, a distance of one third of a mile. In each pipe

was placed a cable of sixty conductors, the wires insulated with gutta-percha, and wound separately with a layer of tarred tape, the whole covered with a double layer of heavy tape tarred and run through sand to prevent sticking to the pipes.

These cables were connected to the submarine cables running to Jersey City. In 1876, a 12-conductor cable about 2,200 feet in length was laid between the main office, 195 Broadway, and the branch office on Broad Street. Owing to the proximity of steam pipes and the destructive effect of gas on the insulation, these cables were short-lived. In 1880, a new 28-conductor cable was laid between the same offices. Before the end of 1882, eleven of the conductors were useless. In May, 1882, sixty circuits were laid between 195 Broadway and 134 Pearl Street, only to be abandoned within a year, every circuit having failed within seven months. On November 28, 1888, it was stated that the result of the Western Union

experiments during the past twelve years proves that there is no form of underground cable and conduit which can be depended upon to give more than four or five years' service under the most favorable circumstances.

In 1878, John P. Barrett, superintendent of the city telegraph system, placed the fire-alarm and police signal wires underground for a distance of 840 feet on a handsome residence street in Chicago. Two-inch iron pipe, the interior of which was heavily coated with tar, was laid underground and into this pipe two kerite insulated wires were drawn. Ten years later it was stated that these wires had given no trouble and were in 'practically as good a condition to-day as when so placed.'

Submarine telegraph cables were in use thirty years before the first telephone exchange was opened. Referring to the first one used in this country, Henry A. Reed said:

This cable was of No. 9 iron wire, insulated to the thickness of half an inch and was made in 1847 by Stephen Armstrong in Brooklyn, N. Y. It was laid across the North River at about Fort Lee. It only worked a few days when it was dragged out of place by a ship's anchor. The first iron-armored cable was made by S. C. Bishop in 1852, and was used across the North River, above Cold Spring. This cable was of No. 14 copper wire with an insulation the size of No. 0, protected by jute and armored with iron wire about No. 8.

Submarine telephone cables were used in 1879 by several companies in crossing rivers and bays, notably in Chicago and Milwaukee, and Patterson telephone cables were placed in the Washington Street tunnel crossing under the Chicago River, in 1879, as previously stated. But probably the first telephone cables that formed a part of a regular underground system were laid in Pittsburg in 1881, by Henry Metzger. Three lead-covered cables were laid on Fifth Avenue between the exchange and a distributing pole, about a thousand feet distant. The cables were composed of 50 single conductors of No. 26 copper wire, and were placed in a wooden box, 6 x 8 inches, made of one-inch plank, that was then filled with asphalt and laid inside the curb below the frost line. No manholes were used, but connecting wires were spliced with a T-joint. In June, 1882, Mr, Metzger laid eight more Patterson cables underground, the longest being 2,200 feet in length, composed of No. 18 B. & S. single copper wires. These cables gave good service for a number of years. That same year, 1882, the New England Telephone and Telegraph Company laid two Patterson 50-pair cables in Boston, for metallic circuit service. The lead-covered cables were drawn in iron pipes laid in cement. One cable was 1,200 feet and the other 1,485 feet in length; both were composed of No. 22 wire, cotton covered. One was laid in Pearl Street in October, the other in Franklin Street in November, 1882.

On May 20, 1882, Professor Chas. R. Cross, in considering the various electrical problems involved in the introduction of underground telephone cables wrote:

In the first place it should be remembered that the number of wires in foreign cities is probably not more than one fifth as great as in American cities of equal size. Thus in Bruges, Belgium, a city of 50,000 inhabitants, there is but one telegraph office, that at the railway station; in Ghent, with 120,000 inhabitants, there is but one telegraph office; in Antwerp, with its enormous commerce, there are but two, one being at the railway station; and in Brussels proper, only one office except at the railroad stations.

In London and Paris almost all messages are sent from the outlying offices to the central telegraph office oy means of pneumatic tubes, and the telegraphic despatches sent from there. From these facts it will be seen that the absolute number of underground wires in foreign cities is much less than is popularly supposed. Contrast in this respect Boston and suburbs, with 377,000 inhabitants and forty-nine telegraph offices, and Brussels and suburbs with 315,000 inhabitants, and eight or at most ten offices.

In April, 1882, thirty-eight sections of a lead-encased telephone cable were laid underground between the two tracks of the Boston & Providence Railroad extending from the depot in Attleboro to West Mansfield, a distance of about five miles. The cable was made by Eugene F. Phillips in sections of five hundred and thirty feet, and connected by means of junction boxes, and he gave the readers of the Electrical World (March 4, 1899), an interesting account of the manner in which the cable was laid. In part, Mr. Phillips said:

In 1882 the American Bell Telephone Company, wishing to make some practical experiments on telephonic transmission with underground wires, ordered of us a cable to be 5 miles in length, containing twenty-one wires of No. 20 B. & S. gauge, a majority of which were to be insulated with rubber and the balance braided with cotton and paraffined; part of the conductors to be covered with tinfoil, and part twisted in pairs for metallic circuit; also a single conductor of No. 13 B. & S. gauge braided and paraffined. We believe this was the first underground experiment made for the American Bell Telephone Company, and the laying of this cable was a red letter day for us. The American Bell sent an engine and one open-end freight box car, which carried the 5 miles of cable we had already made to Attleboro, as well as fifty men for a working force. In laying this cable a trench was started by means of pick and shovel, but it was soon found the hard roadbed was by no means easy digging. A plow was borrowed of one of the farmers and attached to the outrigger from the truck of a car, pulled by an engine. As we were unable to hire oxen or horses to plow with, this idea was suggested by W. H. Sawyer, and it made a fine specimen of plowing, the like of which was probably never before witnessed. When the trench was completed, two plows had actually been consumed in the process. The cable was placed at the end of the car and paid out into the trench as the car moved along, and close behind the plow in the furrow. The filling of the trench was also another great conundrum; the gang started with shovels and hoes to do this, but it at once became evident that it would be a week's work with the force at command. Again Sawyer's inventive genius came to the rescue. At his suggestion a joist was procured, and one end lashed to the cowcatcher of the engine, the other end extending out over the trench on the side where the dirt had been thrown. The engine was started, and the entire length of the trench and cable was soon covered, much to the pleasure and satisfaction of those looking on as well as those responsible for the filling.

Notwithstanding that prior to 1890 no underground system proved satisfactory from a telephone engineer's point of view, yet the rapidity with which the telephone companies responded to the public demand that the wires be placed underground is apparent from the fact that while the underground movement started in 1881, at the close of 1884 there were 1,225 miles of wire underground, and ten years after the first telephone cables were placed underground, over 70,000 miles of wires were in subterranean ducts. To-day over one half of the total mileage of telephone circuits in use by Bell subscribers is underground, that is, nearly three million miles of copper wire are buried in the earth.


XII. The Effect of Electric Street Lighting ox Telephone Service

While an inability to dispose of the securities of the local companies retarded the growth in subscribers in many exchanges, in 1883-5, other causes were also hindering the expansion of the telephone industry. One cause was the rapid introduction of electric-light circuits, so poorly insulated as to sadly interfere with good telephone service and necessitating the rearrangement or reconstruction of many telephone circuits. As already stated, the first street lighting occurred in Cleveland in April, 1879, with Brush arc lamps. In San Francisco the Western Electric Light Company was organized by G. S. Ladd, and on February 6, 1879, was supplying current for private service according to The Bulletin, which said:

Yesterday the Western Electric Light Company made connection with the Gold & Stock Telegraph Company, and now all the electricity used in running their stock indicators throughout the city is supplied from the Gramme machines, thus doing away with five hundred cups, which heretofore composed their battery.

It is stated that arc lamps were in service in San Francisco in October, 1879, the rate then charged being $10 a week when burning from dark till midnight.

It was fortunate for the continued broadening of the telephone industry that it got a strong foothold before the parent electric-light companies began to devote their energies to belittling each others machinery and motives, or to determine whether it was wiser "to advocate the use of sixteen small single light arc machines, with their costly system of conductors, or one sixteen-light arc dynamo," instead of perfecting the insulation on pole line circuits, even if they did not increase the efficiency of their apparatus. Otherwise the electric transmission of speech might have had a different growth recorded. For the character of the crude and cheap telephone construction prevalent in 1878-80 would not have been tolerated by the public in 1882-3, by reason of the number of violent deaths resulting from accidental contact with live wires, deplorable accidents that started a rabid agitation in favor of placing all wires underground. No underground system suitable for telephone circuits was then in existence, and had one been available, the heavy initial cost of installation would probably have deterred many investors from entering the telephone field under such unpromising conditions.

In New York state alone more than a hundred electric-lighting companies, having an average authorized capitalization exceeding a million dollars each, were incorporated before the close of 1883. And as the electric lighting industry was raw and untried, as suitable or even satisfactory line insulation had yet to be devised and tested, and as competition among electric-light companies in many sections was destructively fierce, it is needless to say that the unsafe construction of the average competing electric-light company was such a menace to the satisfactory continuity of telephone service that telephone managers were compelled to forego making verbal or written indignant protests, and to devote every moment of time to devising methods and means for protecting their equipment from the destructive effects of stray currents. Even then, imperfect protection resulted in the complete or partial destruction of several telephone exchanges. Following the destruction of one exchange, Mr. A. S. Hibbard suggested that in view of the delay in getting large switchboards in emergencies, it would be a wise thing in the way of insurance, if a number of telephone companies would jointly buy a complete central office equipment, to be built and held in convenient storage, with the understanding that it should go to the first company whose exchange was burned, and that, that company would pay its cost price or replace it with new equipment.

Referring to the introduction of electric-light circuits, Mr. W. J. Denver told the members of the Boston Electric Club:

I remember the first time the arc lights were exhibited in my native city, and what a tumult was caused at the telephone office. An electric light circuit was strung, using the ground for a return and four or five lights were placed upon it. Immediately on the starting of the dynamo, up went the lights and down went the switchboard drops, and the confusion of tongues consequent upon the building of the tower of Babel was as the stillness of death compared to the racket on the telephone wires. ... The remedy was evident; double the light circuit, which was done the next day.

When the electric-light industry started, the electric lighting fraternity turned to the telegraphers for assistance and advice, just as the telephone men did. But the electric-light men also had the advantage of the experience gained by telephone men in building local circuits. It is written that the first electric-light switching devices were derived from the telegraph switch, only enlarged to accommodate the greater volume of current. The strap key, the telegraph key and the switchboard plug were all utilized in central-station electric lighting, and the arc that formed between the terminals following the withdrawal of the plugs was usually blown out with the breath, or whipped out with a cloth, or extinguished with a handful of sand.

In other words, the same degree of crudeness was just as strongly in evidence in primitive electric-light plants as in the pioneer telephone exchanges. And, as one writer stated it in 1882,

there are electric-light charlatans as well as medical quacks, charlatans totally ignorant of the electrical laws, and with no experience in electric lighting.

One point worthy of note is that the telephone engineer soon found that he must not only be able to solve telephone problems, but must also be thoroughly conversant with every phase of electric lighting, and then of electric power and of electric traction that was in any manner likely to have a bearing on or to influence the character of telephone service. Thus, as the editor of The Electrical World has so concisely stated:

In the telephonic engineering done by Carty and his colleagues there is no parallel whatsoever to be found in any other branch of electrical engineering.