We have to use a more powerful current to make the bell ring, but the telephone itself is so sensitive that we have to guard against any excess of current. On this frame here, we have lightning arresters, heat coils, and fuses that will melt through if too heavy a current should come over the wires, as, for instance, if any electric-light wires should happen to cross one of our wires. Over there on that frame, the wires are sorted out, arranged in groups, and connected with the switchboard above. Before we go up there, I will show you the battery room.”
‘There, for the first time, we began to see some life. Not in the batteries themselves—they were as dead as all the rest of the system—but in a frame alongside in which there were hundreds of little can-like boxes; “line and cut-off relays,” Mr. Burt called them. They were clicking oafter the other, here one and there, all over the frame. Mr. Burt explained that these relays switched in the extra current to light the signal-lamps at the switchboard.
“Now for the switchboards, the most interesting part of all,” said Mr. Burt, as he led the way to the floor above. When he opened the door, I imagined he had taken us into a beehive. There was a steady hum, like the droning of bees. It took me a minute or two to realize that the noise was the talking of scores, yes, hundreds of girls. We could n’t see them all at once, because the room was shaped like a ⏋; but as we walked on around, we found that the entire outer wall was lined with switchhoards before which the girls were seated on high stools so close to each other that they nearly touched elbows. Each one had a receiver at her ear and a horn-shaped transmitter hanging before her mouth, That left both hands free to work, and those hands were certainly busy, picking up “plugs” on the ends of cords and sticking them into holes in the board in front of them. The cords were crisscrossed all over the board, while colored lights flashed up here and there, and, above all, that droning sound. If you stopped to listen to any particular girl, you could hear her saying, “Number, please,” “Audubon 12953, Cortlandt 10476,” “Line is busy,” etc.
“Looks pretty complicated, does n't it?”
“Well, rather,” I exclaimed, “I can see that it would take a week of hard study to understand it all.”
“But it is really very simple, you know,” said Mr. Burt. “If you could only forget that there are thousands of circuits here, you would understand it very readily. It is the repetitions that make it seem so complicated, Now, this switchboard is divided into two parts. We call one the ‘A’ board, it takes up about two thirds of the room; and the other is the ‘B’ board. Suppose you were a subscriber connected with this central, and wished to call up some one also connected with this central. As soon as you took your receiver off the hook, a lamp would light up somewhere on the ‘A’ board, and any one of three or four girls who were nearest that lamp would put a plug on one end of a cord into the jack of your circuit, and say, ‘Number, please.’ As soon as she received the number, she would put the plug on the other end of the cord into the jack, or hole, of the number you called. Now, that is simple enough, is n’t it? You see, she has within her reach the lines of all the subscribers of this central station.”
“But suppose [ wanted a subscriber in some other central?”
“All right. Say you wanted five thousand and something Murray Hill. Your ‘A’ operator would repeat the number to a ‘B’ operator at Murray Hill, The ‘B’ operator would tell the ‘A’ operator to use trunk line No, 8, we ‘ll say, and then would put the plug on the end of that trunk in the jack, or hole, bearing the number you called for.”
“Do you mean every girl has five thousand of those holes, or jacks, as you call them, within reach without leaving her chair?”
“Yes, ten thousand. In each panel there are seventeen hundred jacks, and each girl can cover six panels by reaching across her neighbors. The panels in sets of six are repeated many times all along the ‘B’ board, so that every ‘B’ girl has, access to every subscriber of her central station.”
“It is n’t so very hard to understand, after all,” I admitted.
“I thought you would find it simple, and it ’s quick, too, is n't it? In Paris, not long ago, a record was made of the time it takes to call up a subscriber, and the average was found to be 1 minute 208 seconds. Here in New York the average is eleven seconds! It takes training to do that. We have schools for the girls, and we pay them while they are learning the trade. We have schools for boys, too, who want to go into the telephone business. When you graduate from college, you had better come around. We pay students well while training them.”
Will was interested at once, and asked all sorts of questions, but as for me, I kept quiet. I was n't going to college. I had no rich Uncle Edward to help me out.
Chapter XV
IGNITING OIL BY COMPRESSION
Vol. XL—137.
