In the next few postings, I will show pictures of lever frames and signals shot from the train on two journeys in the Abruzzi. Many of the pictures left me puzzling how the levers were connected to the signals—and I'll share all these puzzles with you, also in the hope that some of you know answers to some of my questions.
Here is my first puzzle picture, of a lever frame at Cerreto d'Esi on the line from Albacina to Macerata and to the Adriatic Sea. Below the picture, I'll ask my first two questions:
Lever frame, Cerreto d'Esi, May 1990
We see a simple lever frame with levers for two home signals and their corresponding distants. Safety is accomplished with simple means: Chains lock the home signal levers to locks that are fastened to the wall; and simple retentions prevent the distant signals from being cleared unless the home signal levers are reversed. The levers turn wheels, and the wire cables are wound around them. But—we will see in a moment that the station had typical semaphores, whose arms where pulled by single wires: What about the second wire end? So my first question is:
Question 1: How are the double-wire levers connected to the single wires to the signal?
Of course, there could be counterweights at the open ends, somewhere below the levers. I am not completely happy about this explanation, first of all, as I would like to see these weights in a drawing or photo; but second, because it is certainly necessary to adjust these counterweights somewhat, for different friction and forces in the single wire lines. How would this work if the weights are suspended in some well below the levers? Again, one could argue that slotted disks as weights could be easily placed there—but this is just some theorizing on my part, which I'd like to be confirmed or rejected.
Next problem: The lines to the distant signals contain compensators. This explains why the rolls on the distant levers are larger than for the home signals—after all, the compensator (as one can see in my posting about Rapolano Terme reduce the wire travel. However, the ratio of the wheel diameters at the compensator is about 2:1; but the ratio here at the lever frame is about 3:2. Why that difference—aren't the distants' arms cleared as far as the home signals' ones?
Question 2: Why is the ratio of the wheels of the levers about 2:3 and not 2:1, as it is at the compensators?
These are all my questions for this posting—more will follow in later ones.
A next photo shows a crank for some barriers:
Crank for barriers, Cerreto d'Esi, May 1990
Back to signals: Leaving the station, I took some pictures of the signals and related facilities. The first one is, of course, the home signal, photographed from the rear end of the train. It is a customary Italian, single-wire pulled semaphore:
Home signal, Cerreto d'Esi, May 1990
Between the home signal and the distant signal, there is the compensator. One can clearly see (at least when magnifying the picture) the single wires, and that the wheel diameter ratio of the compensator is almost exactly 1:2:
Compensator and tensioner, Cerreto d'Esi, May 1990
Next is the distant signal, which I first took from its back side. Again one can see the single wire nicely:
Distant signal, Cerreto d'Esi, May 1990
Then, there is the front side of the distant signal:
Distant signal, Cerreto d'Esi, May 1990
Finally, here are the marker signs indicating the distant's position. Far away, one can see the distant signal a last time:
Distant signal marker signs, Cerreto d'Esi, May 1990
That's it from this small station—I'll show similar, but also somewhat distinct frames in following postings, with their own new puzzles!
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