More Italian signal lever puzzles - episode 3: Pollenza

Deutsche Version dieses Postings

On our way to Macerata we passed this sign for a level crossing. Far in the background, behind the road overpass, one can see the flashing light actually securing the crossing:

Level crossing warning post, near Tollentino, May 1990

The next picture shows a typical distant light signal with its approach sign. I am not sure where I took this photo:

Distant signal, Tollentino?, May 1990

But here is the next lever frame! The following picture mainly shows mister traffic director in front of it:

Interesting signal lever frame, Pollenza, May 1990

The enlargement below shows more details: On the right, there is a typical crank for barriers. The lever frame proper consists of four signal levers, whose wire rolls are all of the same size, and quite a large one at that. Most probably, the four levers are used for two distants and two home signals. The same size of the wheels could either be the consequence of all signals having compensators (which seems uncommon); or none of them having a compensator (also uncommon); or that the angle the levers are reversed is different for distant and home signals (would be very uncommon). My questions are:

Question 3: How are these levers connected to the single wire lines leading to the signals?

Question 4: Why do the wheels for all signals have the same size? Are there no compensators, or do all signals have compensators, or are the reversal angles different for the levers?

Below the levers, there seem to be some locks, which would then need "some linkage" to lock the wheels (or the handles?) of the signal levers.

Interesting signal lever frame, Pollenza, May 1990

Unfortunately, this is the only picture I have of this type of frame.

On our way to the next station, I took a photo of the distant signal out of the rear of the train:

Distant signal, Pollenza, May 1990

... here it is enlarged, to show to romantic situation between all these trees:

Distant signal, Pollenza, May 1990

And here is a picture of the unoccupied driver's seat at the rear of the diesel railcar:

Driver's seat of an FS ALn 668, Pollenza, May 1990

No new puzzles of Italian semaphore levers in episode 2: Matelica und Castelraimondo-Camerino

Deutsche Version dieses Postings

In Matelica I photographed the signals when we arrived at the station:

Distant signal, Matelica, May 1990

Home signal, Matelica, May 1990

Here is a picture of the station buildings, with its massive canopy that had obviously been added later:

Station building, Matelica, May 1990

The lever frame was of the same type as at Cerreto d'Esi:

Lever frame, Matelica, May 1990

Here is an enlargement showing the numerous locks above the levers:

Locks above lever frame, Matelica, May 1990

The following enlargement shows the lower part of the frame, with the wires going down (and letters A, B, C, D on the lever supports). These wires must somehow be connected to the single-wire lines to the signals; with the complication that the wires for the home signals must be pulled when reversing the lever, whereas the wires for the distant signals must be released, because there is this compensator in the line (which in turn requires the different diameters of the rolls). I would have expected that one can see this difference somehow already here, where the wires vanish into the pit below—but this seems not to be the case. The only interesting detail is that the back wires are not parallel, but seem to diverge a little—so they cannot be all vertical, and hence not directly connected to a counterweight. But I cannot guess which sort of mechanics is down there (or somewhere else?) which moves the single wires correctly.

Wires vanishing below the lever frame, Matelica, May 1990

Also Castelraimondo-Camerino had the same type of lever frame, but it is hidden by the signalman on the only picture I took:

Lever frame, Castelraimondo-Camerino, May 1990

Here is an enlargement from the blurred picture:

Lever frame, Castelraimondo-Camerino, May 1990

On leaving the station, I took photos of the signals. Both are mounted on gantries, and both had gotten solar cells, probably for feeding batteries for the signal lamps—an interesting late modernization of these old semaphores:

Home signal on gantry, Castelraimondo-Camerino, May 1990

Distant signal on gantry, Castelraimondo-Camerino, May 1990

So much from these two frames that introduced no new puzzles—more will come in following postings.

The puzzles of Italian semaphore levers - episode 1: Cerreto d'Esi

Deutsche Version dieses Postings

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!

Wire compensator in Swiss single-wire signal lines in 1885

Deutsche Version dieses Postings

Unexpectedly, I found a reference to a single-wire compensator in Hans G. Wägli's "Hebel, Riegel und Signale": In 1885, at least, such a apparatus was present at a small station in Switzerland, shown on the following plan from page 176 (click opens a somewhat larger image):

"Abschluss-Signal" is the term for a home signal, which was at that time still an "outer home", i.e. far enough from the first set of points so that a train could stop before the points if the signal was not cleared.

It is interesting that that Swiss compensator was located about a third from the signal. I do not know why one would choose this ratio—in principle, one could also make the two coupled rolls of equal size, or of any other ratio.

The plan also shows a compensator on the opposite side. That compensator is not located so nicely at one third—however, the plan is not really to scale.

I do not know where these compensators originated—are there any in Britain, or have there been? I'll scan Wägli's extensive citation list, maybe some interesting article or book turns up that might explain this.

Last, but not least, there are also "Annet-Schlösser" in this plan. These are obviously Annett's locks, which lost one T somewhere between England and Switzerland.

"Hebel, Riegel und Signale" by Hans G. Wägli, 2018

Deutsche Version dieses Postings

One of my Christmas presents was quite heavy: "Hebel, Riegel und Signale" (Levers, Locks and Signals) by the late Hans G. Wägli, published by himself in 2018 in Switzerland. Wägli describes, on 450 pages, unbelievably many details of the history of Swiss mechanical lever frames, with many excursions to Germany (where the main suppliers, Jüdel in Braunschweig; and Schnabel & Henning, later Bruchsal, were located), but also to France and Britain. The book is only available in German, but its many pictures could make it intersting also for international readers.

One of the details I found is about compensators—unexpectedly, there is a diagram on page 176 which shows that single-wire lines for signals were used also in Switzerland, at least in the 19th century. The book proves, in my opinion, that the mutual influence in signalling technology among European countries was more extensive than is commonly assumed, at least in the 19th and early 20th century.