I’ve seen several references, including the master himself,
claim that in the early days of railroad signals, a red lens fell out of a signal, and the engineer, who saw white, thought he was safe to go and did, resulting in a major accident.
Did this actually happen, and if so, when and where. Cecil says “about 1914” while other sources say “1914” FWIW.
Being from the UK; I can give, for what it’s worth, what I understand to be the comparable scenario on British railways. So far as I know, over here we never had the part (mentioned in the link) of the convention where green meant “caution”, whilst red = danger / stop and white = clear / go. For a long while, British railways did largely employ red light = danger, white light = clear – though to some extent, different railway undertakings used different conventions.
White light = clear was found in Britain, from early on, a considerable source of potential confusion and danger; and the cause of a couple of nasty accidents – though not AFAIK over here, because of a red spectacle lens falling out – just that there were at night so many other, unrelated, white lights around. In 1892, the UK’s Board of Trade made mandatory for all the country’s railways, green signal lights for “clear / go”.
Britain’s railways were rather slow to catch on to the idea of a specific signal indication for “caution” – it became widespread here, only around the turn of the 19th / 20th centuries; when it did, yellow was used: a yellow semaphore-signal arm, linked to a yellow light for night-time.
In the USA, most signals are of the multi-lamp type, with the red on top and green on the bottom position (no white at all). So even if the red lens fell out, the position of the light on the top signal would indicate to the engineer that this is a (damaged) stop signal.
That is currently – back around 1914, it probably was different in many locations.
I really don’t see this happening. At least, not in a very long time.
There are several types of railroad lights, but for example, the 3 light head has the following meanings. And as you’ll see, a missing lens would really not do much in the way of clearing a train for high speed (speed limit) travel.
3 light head.
Lights are either red, yellow or green.
In fact, there’s a fail-safe that reverts lights to red if there’s a light failure. (they use rotating lenses to make the colors)
Three light signals (3 lights on a signal- like traffic light)
Green light over red light over red light. = go speed limit.
Top light is high speed, Middle light is medium speed (30 mph), and the lower light is slow speed(15 mph)
Top Red, middle green, bottom red = 30 mph. (middle light = 30 mph and it’s the green)
Top red, middle red, bottom green = 15 mph. (lower light = 15 mph, and it’s the green one)
All three red, obviously, stop.
Because this is a train, and trains don’t accelerate or stop quickly, there’s a need to know in advance what will be coming up in the next few miles on the next signal.
Now, add the yellow light for that purpose.
Yellow on top, Red in middle, Red on bottom. = it’s okay to pass this signal at the speed limit, BUT the next signal will be a stop signal. (clear to stop signal).
Red on top, Yellow in the middle and Red on bottom = yep, (middle light is mid speed, or 30 mph) pass at 30 mph be ready to stop at next signal.
Red on top, red in middle and FLASHING yellow on bottom. = Slow (15 mph) and next signal will be a stop signal.
Red on top, red in middle, Yellow (solid) on bottom. Go 15 mph, or slower, but be ready to stop within 1/2 the visual range. (when crossing switches, or rounding curves) In theory, this keeps 2 trains approaching each other on the same track from hitting.
I don’t remember the code for the single light system, or the semaphore signals (the moving arms)
As you can see, there’s no way a missing lens would do much but slow or stop a train.
And this may have even changed with the RCS (rail control)