Story: Movement of Trains - 1911
The following article is from the August 11, 1911 issue of Locomotive Firemen and Enginemen's Magazine. It relates the conception of operating trains on two or more track automatic block signal (ABS) territory without train orders. This occurred during the winter of 1903-04 on the Lake Shore & Michigan Southern "Air Line" (Toledo to Elkhart) when trains were delayed and the dispatchers couldn’t write train orders fast enough to keep them moving. [Contributed by Tim Parker]
Movement of Trains
By G. E. Collingwood, August 11, 1911, Locomotive Firemen and Enginemen's Magazine
A correspondent writes me as follows: “I see that you are the chairman of the Train Rules Committee of the Train Dispatchers’ Association, and I am writing you to know if you will explain the method of handling trains on three and four-track roads, like the Lake Shore, or the New York Central. I understand that train orders are not used to any great extent on the Lake Shore.”
The Lake Shore and Michigan Southern Railway has been operated under a “no-order system” since the winter of 1903-04 with highly satisfactory results. It is truly said that necessity is the mother of invention, and there is no exception to be taken in this case, and the author is glad to be able to state that he suggested the method which led to the adoption of the no-order system upon the above-named road. The necessity for a change became apparent during the hard winter of 1903-04, when passenger trains were being badly delayed by heavy snow in the East; freight traffic was very heavy, and it was found impossible to issue orders fast enough to keep traffic moving. At this point the author suggested that freight trains should be given authority to run ahead of first-class trains until overtaken or until the dispatcher directed them to take siding for a passenger train or some following freight train to pass. This plan met with the approval of the management and it was immediately put into practice on the Michigan Division, under Superintendent Horgan. It worked out so nicely that it was extended to all divisions within a very few days.
The plan was to put out an order at each end of the division, directing all freight trains to run ahead of passenger trains until overtaken. This plan had the effect of permitting free movement of freight trains and that, too, without interfering with the passenger traffic. Freight trains were closely watched and when a passenger train was closing up behind a freight the freight was directed to take siding and permit the passenger train to pass. This was the beginning, no changes having been made in the rules. Later the rules were modified to cover the situation without the necessity of issuing an order to freight trains to proceed ahead of passenger trains. The rules governing this operation are substantially as follows: When a train is ready to leave its initial station it notifies the controlling signalman, who, in most cases, is the signalman operating the interlocking plant, at the initial yard, over which trains must pass when leaving, and when this signalman clears the block the train will proceed without orders ahead of all superior class trains until it is directed by the train dispatcher to take siding to let a following train pass. When a train is ready to leave its initial station the controlling signalman notifies the train dispatcher and clears the train or holds it as the train dispatcher may direct. After a train has been directed to take siding to let a following train or trains pass, it must not again foul the main track until it has obtained permission from the operator at such point, such permission being obtained by the operator from the train dispatcher. This system is a great help to trainmen in many ways, particularly in that the enginemen and conductor do not have to keep tab on a fistful of train orders.
When a train is turned at any intermediate station or when a train is started from an intermediate station, it is required to report to the train dispatcher and get permission before going on the main track.
A train does not receive any orders to run extra, neither does it display white signals; when it is ready it simply reports to the controlling signalman, and when cleared it proceeds as an extra to the end of its run. When a train is directed to take siding for a following train to pass, a message is handed to the engineman and conductor in the same manner in which a “19” train order is delivered, except at stations which have yellow signals. When a yellow signal is displayed at a station it is authority for the train to take siding at the next station, where it will report to the operator and receive instructions as to what trains are to pass it. After the trains have passed, it again reports for permission to proceed. All of the above movements are restricted to portions of the road on which there are two or more tracks and also to movements with the current of traffic. When a train is run against the current of traffic it receives a regular train order in the standard form. Any train having work to do, or which is liable to be delayed by any cause, must report to the train dispatcher and will not occupy the main track on the time of a first or second-class train without orders to do so. Accordingly, a work train must clear the time of all first and second-class trains unless it gets orders against such trains; also local pickup runs cannot stop on the main track to do work without first obtaining permission from the train dispatcher to do so. This arrangement puts the train dispatcher in complete control of the situation the same as where Standard Code rules are in effect. The entire system is fully equipped with automatic block signals.
Where three tracks are in service, two of them are for trains moving in one direction and the other one for trains in the opposite direction. In such cased the direction in which one track is used is down grade, the direction in which the other two tracks are in use being up grade; the outside track is used for freight trains. Where four tracks are in service the two outside tracks are used for freight traffic and the two inside tracks for passenger traffic; however, fast freight trains are permitted to use the high speed tracks when no passenger trains are close and when, by doing so, the fast freight can be run around some slow freight train. Under such circumstances trains take the track for which signal is set, except that passenger trains are not permitted to use the slow speed tracks without instructions to do so. This precaution is taken to prevent a towerman from putting a passenger train on the slow speed track in error.
The rules further state that the instructions to proceed ahead of superior trains must not, in any case, be construed as relieving trainmen from fully protecting their train by flagging.
The automatic signals used are of the semaphore type, two-arm signal, the upper arm being the home signal and the lower arm the distant signal for the next block in advance. Therefore, if both arms show clear it indicates that the two blocks in advance are clear, but if the upper arm is clear and the lower arm at block it indicates that the first block is clear but the next block in advance is occupied. The normal clear indication is used. When both the home and the distant signals are at block the train must be brought to a stop, after which it may proceed under caution, expecting to find another train in the block, or perhaps a broken rail or an open switch.
In the case of accident on one track trains are diverted to another track, and when this involves a movement against the current of traffic train orders are issued. For example, if No. 1 is to be run against the current of traffic from B to C, the order would read, “No. 1 has right over opposing trains on No. 2 track, B to C.” Such an order is not to be issued until No. 2 track has been cleared of all opposing trains; but if No. 1 is required to wait at B for No. 4 to arrive, the order is made to read, “After No. 4 arrives at B No. 1 has right over opposing trains on No. 2 track, B to C.”
There are several other methods of handling traffic on double-track systems, but I do not think any of them is superior to the system under which the Lake Shore operates.
Reference: Locomotive Firemen and Enginemen’s Magazine, August, 1911, pages 201-202
Tim Parker notes: Eventually this was handled by take siding signals (Rule 293a) which had a normally dark head lower and to the right of the block or train order signal and controlled by the dispatcher or operator. When I first started working on the MC main in 1970, I could tell where some of the old sidings had been removed as they hadn’t removed the take siding signal heads. By this time the dispatcher would simply call on the radio rather than mess with the signal although one Jackson dispatcher would do both.
From Jerry Pinkepank: I have a 1904 CB&Q rule book loaned to me which contains operation by signal indication only. The idea may have spread quickly. The overtake part of what was done in this narrative is, of course, what became Rule 251-254 operation on all roads using the standard AAR rulebook (which everyone had variations on, but the fundamental rules carried the same number from road to road). The operation by signal indication only was in some respects a rediscovery of this idea, since the very first block signals in the United States, on the predecessors of the PRR in New Jersey, and then on PRR proper after these lines were acquired in 1868, were used to advance or hold trains without the use of train orders. Furthermore, since the PRR had a tower every seven miles on multiple track, it was not necessary to have a route signal, though there obviously had to be some means of slowing a train to turnout speed if it was diverge (probably done with flags and lanterns except some towers were, I think, equipped with illuminated track indicators.) By the way, having first learned signal aspects on the GTW, I was not aware of the NYC’s use of speed signals, and when riding a T-motor into Grand Central on my way to school one year, and observing one of the four-head aspects that were able to provide for several different speeds depending on the type of turnout and other controlling factors, I asked the engineer, “Does that mean we’re going to cross over?” To which he replied, “I don’t know, son. I’m not steering”. That story has served me ever since to explain the difference between speed signaling and route signaling. After the BN merger I told the story to Charlie Dunn, the ex-NP signal engineer who had been chief engineer of NP before the merger. The NP was the only speed-signaled road in the BN merger, having a very elaborate system in force between Portland and Tacoma, and he enjoyed having some reinforcement after hearing the endless jokes about signal aspects supposedly providing for “a medium speed during the full phase of the moon”.
From Tim Parker regarding ABS on the NYC (former LS&MS) Old Road: My 1923 Michigan Division employee timetable shows that there were automatic block signals (ABS) on the Old Road's single track from White Pigeon to Elkhart. The Old Road from Toledo to White Pigeon (via Adrian, Hillsdale and Coldwater) was manual block, so it says. The ABS installation (according to the LS&MS history) was put in place between White Pigeon and Elkhart on November 23, 1912. The signals are noted as being three-position upper quadrant semaphores. The distance between White Pigeon and "B" Elkhart is 19 miles and there were signals every mile with the exception of a single two mile gap. ABS normally protects close following movements, but it has much less protection for opposing movements; hence its use on multiple track main lines. When in use on single track, trains must get permission to enter the ABS territory first, then it will have protection from the signals. The short blocks (1 mile long) used on this line were designed to increase capacity. There were sidings at Vistula (425.1), Bristol (with train order station 431.0), and Morehouse (434.3). There must have been quite a bottle neck to install that ABS on 19 miles of track.