Popular Science Monthly/Volume 70/March 1907/Notes on the Development of Telephone Service IV

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NOTES ON THE DEVELOPMENT OF TELEPHONE SERVICE. IV.
By FRED DELAND

VII. Some Early Telephone Switchboards

THE switchboards in the New Haven and other pioneer telephone exchanges were far more crude mechanically than the marvelous and sensitive hand telephone. The first switchboard that Mr. Coy installed in New Haven had a capacity of only eight lines, but as every line was a party-line, and as an average of twelve subscribers were on each line, the board served a hundred or more subscribers. This board was designed and built by Mr. Coy, in December, 1877, with the aid of a local carpenter, and formed a part of the partition

PSM V70 D233 Early telephone switchboard.png
Fig 6.

that separated the office from the battery-room. So far as known no photographs of the exchange or of the board were ever taken, and when the partition was removed the switchboard no longer existed. However, in Fig. 6 is an excellent reproduction of a rough sketch made from memory many years ago, of what Mr. Coy asserts was the first switchboard, though others claim that the board had no annunciator attached during the first two months.

Crude as the construction of the board was. without cords or plugs, clearing-out drops or other improvements that facilitate rapid service on the part of the operator, it was considered a remarkable piece of workmanship in its day, and prospective investors in telephone systems traveled from various states to inspect Mr. Coy's equipment and to study the working method of this first of all telephone exchanges. The switchboard used in the Meriden exchange, opened a few days after the New Haven exchange, is now preserved in the Smithsonian Institution at Washington. It is similar in type to the New Haven board, and was designed by Mr. Coy. The switchboard used in Richmond, Va., as late as April, 1879, had six dials on its face, 'each circle about ten inches in diameter, formed by thirty-nine numbers.'

Service from Mr. Coy's board was supplied after the following fashion. On the shelf was a large induction coil with a manually operated buzzing attachment (Fig. 7). This calling device was known

PSM V70 D234 Induction coil with manually operated buzzer.png

Fig. 7.

as 'Watson's squealer' and also as 'Coy's chicken,' for the shrill squeal it sent out over the line could be easily heard in all parts of a large room. When 'Central' desired to call a given subscriber on a party line, as No. 5, for instance, on party-line No. 8, the operator connected this buzz-box to line No. 8 and sent five long squeals over the line, which would be the signal for subscriber No. 5 to come in on the line, and for the others to stay out.

For the use of his subscribers in New Haven, Mr. Coy hung the mahogany or rubber-encased hand telephone on a steel hook screwed into a black walnut board (Fig. 8) which he attached to the wall of the subscriber's room or office. Binding posts for wire connections were fastened to each corner of this board, with a simple strip type of lightning arrester connecting the upper two posts, line and ground. Near the center of this board and bridged on to the grounded iron telephone circuit, was a circuit-break push button for the subscriber to use in calling 'Central.' Below the push button was inscribed the number of the telephone.

Primitive as this outfit now appears, it was considered a luxury in 1878 that many were glad to have, and practically constituted the entire telephone equipment supplied to subscribers by the early telephone exchanges. For as rapidly as other operating companies came into existence, they copied or adopted Mr. Coy's equipment, modified more or less according to the mechanical or artistic views of the local manager or his manufacturer. A modification used in Richmond, Va., is shown in Fig. 9.

In one sense these magneto systems might be properly termed central-energy exchanges. For though no batteries were required to operate these pioneer hand telephones, all the current required to signal 'central' or 'subscriber' was supplied from a 'common-battery'

PSM V70 D235 Early telephones.png
Fig. 8. Fig. 9.

set of gravity cells maintained in the exchange and operating on a closed circuit.

When a subscriber desired 'Central,' he touched the metal push button, shown in Fig. 8, which actuated a single-stroke bell in the exchange and released a drop in the ordinary house-annunciator attached to the switchboard, thus indicating the respective party-line. On hearing the bell, the boy-operator would leave whatever other work he was engaged upon, walk leisurely over to the board, glance at the annunciator, turn the single switch to the metallic strip to bring his telephone in circuit with the calling subscriber, and loudly enquire: 'What do you want?' then place his telephone to his ear just too late to catch the full reply. Louder explanations on both sides would follow, and sometimes the subscriber's remarks were not of a character suitable for publication, while the replies of the operator partook of the same lurid nature. For there were no sissy-boys and no girls among the pioneer operators of 1878-1880.

Finally, subscriber No. 5 would make the operator understand whom he desired to be connected with. Then the connection was given by turning the lever of one circle to the peg to which the calling-line was attached (Fig. 6), and placing the lever of the other circle on the peg or post connected to the line of the calling subscriber. The boy would then go back to his other work and probably forget all about the two subscriber-lines connected together, until an infuriated individual would rush into the office and demand the reason why some blithering idiot failed to answer his bell. Then the boy would have to pacify the subscriber as best he could by explaining that when two subscriber lines were connected together, the call-bell and the battery-connection on each line were cut out to improve the talking qualities, and each subscriber was connected straight through to each other's telephone;

PSM V70 D236 Forty wire telephone switchboard.png

Fig. 10.

that in the pressure of cleaning batteries, or sweeping the room or doing some other kind of work, boy-like he forgot to disconnect the circuits.

With Mr. Coy's first board two telephonic connections only were possible at the same time. That is, two conversations only could be carried on at the same time. If a third subscriber desired connection, it was necessary to await the release of a lever by the disconnection of one of the other lines. Then the bright thought occurred to the boy operator that by wetting the tips of his fingers and placing them on the respective pegs, his arms would become the levers of the respective circles, and thus the two subscribers could talk through his body. This very ingenious makeshift served to tide over the brief period during which an addition of two more circles was made to the original board, thus increasing its capacity fifty per cent. But one day, while the boy-operator was letting his wet finger-tips perform the service, now taken care of by cords and plugs, the ring-off signal came in from a subscriber who had just had a powerful magneto installed, and the shock received ended that very convenient practice.

PSM V70 D237 Vertical telephone contact bars.pngFig. 11. Soon there were more than 150 subscribers on twelve subscriber-lines, and the ratio of calls per subscriber was constantly on the increase. So a new board was planned by Mr. Coy—and built by Mr. Snell, who is still in New Haven engaged in supplying equipment-specialties to telephone companies. This board (Fig. 10) had a line capacity of forty wires. Evidently switchboards of this type found favor for a time in the opinion of the parent company; for a circular issued in 1880, by the National Bell Telephone Company, contains the following suggestions, all of which were omitted from a circular of similar purport, issued a year later by the American Bell Telephone Company:

There are several styles of switchboards that may be used, all depending on the general principles for their operation. They consist essentially of horizontal and vertical bars crossing one another and arranged so that any horizontal bar can be connected to any vertical bar. It is chiefly in the methods of making the connection that the various switches differ. In what is known as the 'plug' switch, the connection is made by inserting a small metal plug at the point where the horizontal and vertical bars cross one another. There are several forms of the plug switch. . . . In what is known as the slide central office switch, the connections are made by means of a sliding contact plug, which can be moved on the vertical bars, and when placed over one of the horizontal bars, springs into firm contact with it. . . (as shown in Fig. 11). The brass rods for connecting any two lines together are fastened to the walnut frame, and in front of them but not touching, are the upright rods. The line circuits, as they enter the office, are connected to the upright rods by binding screws on top of the frame. Each of the upright rods has a spring-slide which, when pulled outward, can be slid freely on the rod, and which, on being released, springs into firm contact with any one of the horizontal rods with which it may be desired to connect it.

Within a year the increase in the number of subscriber-lines in the New Haven exchange made an additional board necessary. So a Snell board having a capacity for thirty-five subscriber-lines was installed

PSM V70 D238 Snell telephone switchboard and contact jack.png
Fig. 12. Fig. 13

and connected to the old board. The principal feature of the Snell board (Fig. 12) is the Snell jack (Fig. 13). The instructions sent with the board read:

The line connects the levers together perpendicularly. The springs being connected horizontally, form the connecting bars. Any two circuits are connected by throwing the corresponding levers on the same row of springs. We have testimonials from parties using the switch, where one operator does all the work satisfactorily for three hundred subscribers, where with any other system it would require at least two, thus making a permanent saving in the running expenses.

A cheaper type of Snell switchboard is shown in Fig. 14, using what are called 'tip-up jacks.' This board consisted of an

inclined table, having as many grooves, about a quarter of an inch wide and deep, as may be required for connecting bars. Between every third groove is a row of counter-sunk holes for the wire posts inside of a spiral spring; a smaller wire passing through the ends of the posts forms the line and acts as a hinge for the little tip-up jacks, that connect the line with the brass plate on the bottom of the groove. The spring allows the post to give a little, thereby making a rubbing connection and holding the jacks firmly in their place when any two are tipped up on the same groove to make connections.

The combined annunciator recording drop-plate shown on this Snell board is of interest in showing the appreciation in those pioneer days of the necessity of a measured-service system. Five falls of the plate (Fig. 14) would cause one revolution of the shaft, which, in turn, would move the indicating wheel one notch. A later form of switchboard

PSM V70 D239 Snell telephone swithboard and dropjack contact plate.png
Fig. 14. Fig. 15.

devised by Coy and Snell is shown in Fig. 16. A board of this type was installed in Hartford in 1879. In December, 1881, in the Providence exchange there were thirteen Post-Snell switchboards of twenty-five wires each, four of fifty wires and one of sixty wires, arranged on three sides of the operating room, and from these eighteen boards service was supplied to eleven hundred subscribers.

The switchboards adopted by other exchanges were as unique in character as those erected in New Haven. In St. Louis, in April, 1878, Mr. George F. Durant used a 'jump jack switchboard,' the operation of which is thus described:

On the subscriber ringing his bell, the annunciator would fall and the boy-operator would ask: 'What do you want?' Finding out what was wanted, the boy would notify the switchman what connection was desired, which was made by two single plugs attached to a single cord, by placing one of the plugs under each of the jacks requiring the connection.
The second switchboard had brass bars running the entire length of the board, with holes about every five or six inches to insert the plugs

PSM V70 D240 Snell thirty five connection swithboard.png

Fig. 16.

into, and were connected to the disconnecting switch through an indicator and jump jack.

In July, 1878, Thomas B. Doolittle planned and had constructed by Charles Williams, Jr., of Court Street, Boston, a twenty-circuit telephone switchboard, which Mr. Williams has stated 'was the first switchboard completely equipped with signaling apparatus ever made at my establishment.' This board (Fig. 17) was placed in Mr. Doolittle's exchange at Bridgeport, Connecticut, which succeeded to the first mutual telephone exchange system, and is the small board shown in Fig. 18.

In 1877, Mr. Doolittle had made a small six-point cross-bar switchboard for use in Bridgeport, in which he substituted simple switches for the usual telegraph plugs, as the former were more easily manipulated in making connections. Then he brought out the small board above referred to. Meanwhile he devised his 'direct-connecting board' (Fig. 18) in which each line terminated in the board after passing through a single stroke bell, to the hammer of which was attached a hollow brass ball suspended by a silk thread. To each circuit an operator's telephone was attached, and the cords were of sufficient length to reach the furthermost limit of the board. Following a subscriber's call the stroke of the bell set the brass ball to swinging, thus notifying the operator, who cut off the battery by turning a switch and then inserted a plug in the line socket and received the call. The companion cord was then removed from the ground plate and inserted in the socket of the line called for. Mr. Doolittle states that on several PSM V70 D241 Doolittle switchboard connections.pngFig. 17 occasions he saw the operator take care of four calls at the same time by holding two telephones in the fingers of each hand, that is, the operator had to talk and then listen into four separate telephones; in other words, using both ears as well as both hands. Incidentally it may be mentioned that Mr. Doolittle claims that it was on this board that the first female telephone operator was employed. A glance at the illustration shows that the cylindrical wooden weights suspended on the plug cords were about an inch in diameter and a foot in length, with a brass pulley attached to the top of each. These long weights were employed at first in anticipation that their length would prevent the cords from swinging and tangling, but later were displaced by smaller but heavier lead weights.

According to a local paper the switchboard erected in Philadelphia, in December, 1878, consisted of

a walnut frame and braced strips of brass punctured with holes, into which wires are fitted to make the necessary connections. Behind this all the wires converging in the office concentrate. The board accommodates 400 different lines.

In October, 1878, the parent 'Bell Telephone Company' issued a circular describing a form of brass strip switchboard 'adapted for six circuits.' On February 20, 1879, a circular was issued describing a switchboard which could be supplied at

from 50 cents to $1 per circuit, according to the number of circuits. The dimensions of this switchboard for from 50 to 200 circuits are 6 feet long by about 3 feet wide.
Switchboard tap-bells were listed at $2.50 each; subscriber's hook district bells, $3.25 each; spring keys, 75 cents each; lightning arresters, 37 cents per circuit. It was stated that "the following plan it is

PSM V70 D242 Bell telephone co horizontal bar swithboard.png

Fig. 18.

believed combines the advantages of the (thirteen) different systems." A diagrammatic representation of the wiring of a single circuit in this board is shown in Fig. 19. There is also shown a flexible cord attached to a plug and a wedge of hard wood having a metal plate fastened to one side. The instructions sent with the board read:

The local size gravity battery is used—one cell for each bell and for each mile of wire is sufficient. A circuit one mile long having ten bells requires about fourteen cells of battery. Two circuits may be operated by one battery if they are about equal length and I have the same number of bells on each. . . . PSM V70 D242 Bell telephone co connection schematic.pngFig. 19. When any subscriber on this circuit wishes to call the central office he presses his knob twice, which rings the bell; the operator then inserts the wedge between the spring and the plate, with the metal side against the spring, and the plug into a brass strip which is connected through a set of telephones to the ground. This, it will be seen, takes off the battery and connects the telephones so that the operator can talk with the subscriber and ascertain his wants. If the subscriber wants to talk with a person on another circuit, the central office calls that person and on receiving his answer, the two circuits are connected together by inserting a wedge under each spring and putting each plug into one of a pair of brass strips which are connected together through a hand telephone by means of which the central office operator can ascertain when the two persons have finished using the circuits. Then he removes the wedges and plugs and the circuits are ready for another call.

The instructions for the subscribers equipment read:

The circuits are run from the central office and grounded at the last stations. A small electric bell is placed in each subscriber's house or office, having a hook projecting from its base on which the hand telephone is hung when not in use (Fig. 20). When the telephone is removed this hook can be thrown either to the right PSM V70 D243 Bell telephone secure connection handset 1879.pngFig. 20. or left. When thrown to the right the line wire on one side of the station is connected through the telephones to the ground and the line on the other side is opened, preventing any one on that side hearing what is said. When thrown to the left the reverse is true. It is obvious that no person between the two that are conversing can put his telephone in circuit without breaking the line, and consequently, interrupting the conversation. All other stations on the circuit are notified that the line is being used by the striker being away from the bell. In this case the subscriber must not attempt to call or use the telephone. The signaling is done by pressing and releasing a knob the requisite number of times. . . .

On June 12, 1879, the parent Bell company sent out photographs and a circular describing 'our No. 1 standard central office strip switch arranged for seventy-five circuits.'

In November, 1881, Mr. T. D. Lockwood said:

To make a good telephone exchange switchboard, however, out of an ordinary telegraph switch, we concede that considerable remodelling is necessary; and after the first heat of invention was over, practical men began to look about them, to see the disadvantages they were laboring under and endeavor to overcome them. It was seen that time and money were, in telephone offices, the two main articles to be economized. Time, because speed of connection is the very life-blood of the business. Money, because in many of the exchanges the telephone business was managed and owned by men of little or no capital; and, in others, the expense, in any case, would be great, and economy was necessary to make anything at all out of the business. Soon, therefore, it became obvious that the telephone switch must be compact; all the apparatus must be easily and quickly under control; everything about it must be well made and well put together; the motions required in a connection must be reduced to a minimum, and yet the apparatus must be cheap. The cry of cheapness for a long time obscured the vision of the practical man.

In 1881 came the first of the multiple switchboards. This innovation was arranged for grounded and later for metallic circuits, and was designed to eliminate many of the causes tending to slow down the service. Under the previous system each operator was compelled to act as information bureau, and subscribers called by name rather than by number. The introduction of the mutiple board made necessary the assignment of numbers to subscribers, and many an urgent request to call by number rather than by name. Thus the multiple-board operator made connections only in response to requests giving numbers. If complaints were made or information requested, the caller was quickly switched to the information desk presided over by a special operator. In the same manner the toll calls were handled at a toll board or special section of the large board. A 1,500-line multiple switchboard was installed in New York in November, 1883. In 1883 Mr. W. D. Sargent said:

The ideal (switchboard) system would be one in which the operator would receive the orders to connect and disconnect from the subscriber orally, by means of a head telephone; to have in front of her a switchboard by which she could connect any two wires of the whole system, however large, without interfering with the other operators. The nearest approach to this perfect system at the present time is the multiple-board; but this has never been worked on the true or multiple principle, and it can never show all its merits until it is. The multiple-board is now being introduced into many of the largest cities, and we may expect much information during the coming year on its merits.

Now-a-days a new switchboard is often placed in service so quietly that the subscribers are rarely aware of any change taking place until after the work is completed. But in the pioneer days it was somewhat different, as is shown in the following interview clipped from an eastern paper in 1882:

In removing from the old to the new central exchange unforeseen difficulties were encountered, chiefly in the removal of such a mess of wires and the abrupt change from the old system to the new system (of calling), and the

PSM V70 D244 Gilliland telephone switchboard of 1883.png

Fig. 21.

necessarily temporary character of much of the construction. The public had to be personally taught to use the new system, and our operators had to be educated in its rapid use. This naturally caused dissatisfaction, and before the system was tried and the construction trouble was eliminated, our subscribers, through misapprehension of the real purpose of the change, were invited to meet and form an association to protect their interests and compel satisfactory and perfect service on our part. . . . The association was soon compelled to acknowledge the superiority of the new service over that of the old.

In March, 1883, there were thirty Gilliland switchboards (Fig. 21) in the Pearl Street telephone exchange in Boston, and seventy-five toll lines terminated there. These boards stood about a foot apart and were displaced by a given number of multiple sections forming one compact, continuous board. In referring to the installation of the multiple switchboard in this exchange in 1884, Mr. Carty stated that

there were about 1,650 subscribers, ninety branch and thirty extra-territorial lines. The extra-territorial lines were handled by five operators on the 25-wire boards, on each of which there were a dozen or more subscribers. This called for a force of thirty-nine operators on tables at any one time, seven operators for relief and seven night operators, making a total force of fiftythree. With the multiple system only twenty operators are required to fill the boards in the main exchange, with five relief and four night operators. In the toll room, eleven operators are required, including the chief, one relief and two night operators. This makes a total of forty operators, handling 1,700 subscribers, 152 trunk lines, and shows a saving of thirteen operators.

Incidentally, it may be added that the Boston board was put in at an expense of $48,000. The old boards cost over $20,000, but brought less than one tenth that sum when sold as junk, though in use less than four years, and some less than two years.

In September, 1885, Mr. T. D. Lockwood suggested that where the multiple board was to be installed it would be well

to get the numbers drilled into the subscribers first. I was in Baltimore eighteen months ago, when the subscribers were all known by name. They were going to change that, and they were also introducing the multiple boards at the same time; and the operation of the new multiple boards was somewhat premature, because the old boards fell to pieces about a week before the new ones were expected and the change had to be made very quickly, and the change from names to numbers, and from the old board to the multiple board resulted in producing a condition of things very like a pandemonium for three or four days.

That the Western Union's competitive telephone service was of no better character than that of the Bell, notwithstanding its long experience in serving the public and the far greater resources at its command, is clearly portrayed in a description by a Times reporter, of a visit to the Chicago exchange of the American District Telegraph Company, in July, 1879. He wrote:

The racket is almost deafening. There are speaking tubes running all about the room, which look not unlike small stovepipes, and at one end and the other of these are placed the lips of one operator and the ear of another. Boys and girls are rushing madly hither and thither, seemingly without intent or direction; while others are putting in and taking out pegs from the metallic surface of the central framework or switchboard as if they were lunatics engaged in an old-fashioned game of fox and geese.

How different are present-day conditions in the large exchanges, where the operating force is well disciplined and thoroughly trained, and where the modern relay multiple switchboard affords every facility for rapid intercommunication. So compact are these improved switchboards that each subscriber-line reappears in each and every section, thus enabling any one of the three operators allotted to a section to reach the jack connecting with the subscriber line of any one of the many subscribers connected to that given exchange even though they number ten thousand. Under these favorable conditions the average time in which 'Central' answers a calling subscriber rarely exceeds four seconds, and a local call is completed on an average of less than thirty-five seconds, the time consumed depending largely on the promptness with which the called subscriber responds to 'Central's' calling. Concerning the rapidity with which telephone connections were secured in pioneer days, we have a statement made in 1887, by Mr. B. E. Sunny, a man of exceptional ability, who was one of the first to comprehend the true function of telephone service and who strove to make his service the best that human effort and improved apparatus could make it. Mr. Sunny said:

Chicago has tried the division of labor plan on three distinct types of switchboard. On the first switchboard in the central office in about 1880, with four hundred subscribers, we were able to make a connection in about five minutes; on the second type of switchboard, which was the Gilliland, we were able to make connection with five operators in about two minutes. On the third type-of switchboard, which was the Western Electric pattern, but of special make, we came mighty near not being able to make any connection at all; but after we had hammered away at it for a long time, we got the time down to about two minutes and a half. We changed from that to our present system of the unit of labor, and we make connections on an average of about forty-five seconds. So far as possible we make two operators on all connections, local and trunk, do the work.

It is also interesting to note that in 1884 Mr. Sunny started a school of instruction for telephone operators in Chicago. When an applicant appeared she was advised to enter this school and receive free instruction, and about one in four of the students were found competent to enter the regular service. When full, the class was composed of ten students. The teacher in charge was a former public school teacher, who had also served four years as an operator, monitor, chief operator, etc., under conditions that had enabled her to gain a thorough knowledge of the duties of an operator. The school apparatus consisted of three sections of switchboard and a dozen or more telephones connected up at different points in the school-room. Calls were sent in and connections made at the switchboards as nearly as possible according to regular practice. Mr. Sunny found that this method of training

educates the students in the matter of hearing and talking and handling the cords and handling the cam-levers, so that when they sit down to actual work they have nothing to overcome except the momentary nervousness. In the old system we used to take a new-comer and put her on a section to answer fifty subscribers, and we used to depend upon the subscribers to educate the operator and make her competent to fill that position.