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Celebrating the Centennial - 1876

How the Fire Alarm Telegraph is Worked - 1877

Fire Alarm Operations during the Great Earthquake and Fire - 1906

Construction of The Central Fire Alarm Station - 1912

House of Alarm Bells - CFAS - 1937

Fire Alarm Operations during the 1989 Earthquake

Fire Alarm Operations during the Oakland Firestorm


How the Fire Alarm Telegraph is worked.


An Interview with Operator Clarke—
Offical Declaration of Midday—
Reading Smoke in the Air.

The Fire Alarm Office has an important mission to perform, and is intrusted, in a very large degree, with the safety of property and, to no inconsiderable extent, of the lives of citizens. There are a Superintendent, three operators and two line repairers. The operators are on duty eight hours each out of the twenty-four, so that at all hours of the day and night a public guardian is constantly watching, with one eye on the instrument and the other on a book. Photograph of the San Francisco Fire Alarm Office in the Exempt Firemans building on Portsmouth SquareThe office is located on Brenham place, overlooking Portsmouth Plaza, in the third story of the Exempt Building, with two conveniently large windows, commanding a comprehensive view of the entire lower and business portion of the city. A CHRONICLE reporter, in connection with his duty in guarding the interests of the public looked into the office yesterday morning. The operator was seated


Connecting with the various city institutions, deeply engrossed in the absorption of a communication from one of the institutions mentioned. The reporter recognized the son of Counselor Clarke. When the clicking of the instrument had ceased, he welcomed the representative of an hundred thousand people with great cordiality. “How are you?” said he... . The reporter expressed a desire to look over the establishment and have things explained to him. “Well, there isn’t much to see around here. There’s where the boxes come in—on that piece of tape. Some boxes are represented by dashes and dots, others by dashes only, and others by the blank spaces between dashes. We can readily distinguish by the length of the first dash, and never get mistaken in that line. We sometimes experience difficulty in


Particularly those which are not automatic. You know in the automatic boxes a person has but to pull the hook down, and the alarm comes in nicely, if there isn’t anything the matter with the wires. The other boxes are called crank boxes, and to turn in an alarm you must turn a crank around in a certain manner. Most people who turn in alarms of fire are greatly exited, having rushed from a small blaze in their houses, probably with the expectation of returning immediately and seeing their property entirely destroyed. The consequence is that when they seize the crank they remember the instructions to turn slowly and proceed very deliberately in accordance with them. After the first revolution of the crank their mind returns to the fire, their hands get nervous and they turn the crank with a sort of frantic, jerky movement. The alarm, as a natural consequence, does not come in properly, and we are compelled to wait until it is repeated in an intelligible manner before we can determine the exact number of the box turned in. Another trouble is when two boxes come in at the same time, or nearly so. That pointer (pen) there that marks the boxes has to be adjusted after almost every alarm we turn in. The changes of the weather sometimes lower it or raise it too high. When we catch the


We run for the tape mighty quick, I can tell you. If we see a great long dash coming in we know that the adjustment is too high, and when we see the tape moving in with no mark we are satisfied that the adjustment is too low. We accordingly turn that little screw there and either lower or raise the adjustment, as is necessary. Then we have to pause for the box to come in on the tape. When two boxes come in together we can’t tell which is which, most of the time, and we are delayed till we can determine. It’s altogether different with automatic boxes. There is no trouble with them. You see, there are about twenty boxes in a circuit, and while one of those boxes is being turned, no other box on that circuit can be received until it get through. When two boxes come in for a fire it is difficult to tell which boxes are being turned, because the communication being by dots and dashes from crank boxes, or by spaces between dashes, from the non- interference boxes, it is essential that the line be free from interference while the box is coming in, so that the tape may bear the exact impress of the box from which the alarm is sent. When two boxes on the same circuit are simultaneously turned in, the effect is confusion, because the


Of the one falling over the dots, dashes or spaces of the other, render the communication of each unintelligible so long as the double communication lasts. It often happens when a fire suddenly shows much light that persons at a distance from the fire turn in an alarm from a box nearest to them at the same time that a box near the fire is being turned in. This creates confusion, and the operator must educe from the entangled communications the number of the proper box to strike, which requires skill and judgment. We sometimes catch a fire out of the window at night, and turn in an alarm ourselves, but very seldom. We are accustoming ourselves also to the various smokes around the various business portions of the city that we can see from here, because the knowledge may come in useful some day. That’s following out the plan of Boston and some other large cities East. They have men in elevated towers on the lookout there all the time, and the men have become so well practiced in their business that they would surprise you. Of hundreds of some-stacks visible from their towers, and other smoke issuing from pipes not visible, they can pick out any one and tell you


It is—whether it is a factory, mill, shop or whatever it is—what time it commences and what time it quits. They bid all the ’smokes’ as they call them good night and good morning, and new and strange smoke which intrudes itself into the select company is instantly detected by the men, and a messenger dispatched post haste to find out what it is, and if it is a fire, turn in an alarm. If the smoke is voluminous and a stranger to the watchers, they locate it by comparison with some smoke of old acquaintance, and immediately turn in an alarm from the box nearest to the fire. We haven’t progressed as far as that yet, but we can tell a great many of the works. Here’s something you haven’t seen yet, I guess. That’s called the Tell-tale Register. You see it has a paper dial, and the lead pencil attached to it moves up and down every time we test the apparatus. We are required to test every circuit every half hour, and if we miss a half hour during the night there appears a vacant tell-tale space in the dial, and when the Superintendent comes down in the morning he can tell at a glance whether we were attending to duty or not. The testing is a good thing for us, because it serves to keep us awake at night when it’s very lonesome. Sometimes—Hello! it’s almost 12 o’clock. Of course you know we


Every day three times. We have the exact time here, because [Thomas] Tennant, the chronometer-maker is employed by the city to set the clock once a month by the sun. Now, you watch me and you’ll see the whole business.”

The operator crossed the room, and, grasping a knob, gazed at the clock intently as the minute-hand crept slowly around, and when it covered the first character of the “12,” he twitched the knob around suddenly to the figure “3” and made a frantic rush to a marble table adjacent where an array of similar knobs obtruded themselves, and commenced to twitch them around in a similar manner in great haste. Before he had removed his hand from the last knob, however, the absorbed reporter was startled by the sudden clang of the great bell overhead on the roof and the tremulous movement of the house, the vibration of the ponderous bell shaking it as if an earthquake were going on. There were three deafening notes and the music ceased. The operator turned, and as he wiped off his forehead and chin with his handkerchief, remarked: “We’ve got to do that pretty quick, you know, because the people in Hayes valley must have the correct time as well as the people around here. We’ve got the wires connected with gongs in a bag factory and a flouring mill downtown, and the whistles there give every alarm.”

Daily Chronicle
February 11, 1877

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