It seems that during the kerosene and early electric era, headlights were generally positioned on top of the smokebox ahead of the stack. However after maybe 1920 or so, they started getting moved down to the middle of the smokebox door or even lower. Was there actually a reason for the change other than asthetics? I can only think that it would have something to do with larger engines casting the light too far away if positioned on the top but even small engines often had the headlight moved down.

Thanks.

I suspect what is really going on is keeping the headlight at a (more or less) constant distance above the ground for the railroad's fleet of locomotives. Smaller (shorter) locomotives would have had the headlight mounted above the smokebox, while a large road engine, being taller, would have had the headlight mounted lower.

The headlight serves a dual saftey purpose. It illuminates the tracks ahead of the train. The light also provides warning of an approaching train to people along the tracks and at grade crossings.

If the headlights were not mounted at a consistent height, then the apparent distance, and speed, of an approaching train would be different for different locomotives. A person stopped at a grade crossing would have difficulty deciding whether the approaching train was a short locomotive close, or a tall one further away.

Ditch lights further enhance an observer's ability to judge the locomotive's distance and approaching speed.

Then again... it might just have been the mechanical department's sense of asthetics.

That has wondered me too. In the oil headlight days I think they wanted to mount the big thing as securely as possible and clear of the opening of the smokebox door; hence the mount up top.

Electric headlights got smaller and there seemed no rhyme or reason. PRR's were all high; C&O mounted them low; RDG had three favored locations depending on the class of the engine.

Headlights were also signals, marking the front of the train at night, and in older rule books, identifying whether the train was occupying the main track or clear in a siding.

The Western Maryland eventually mounted the headlights high on the smokebox of most classes of their locomotives to give them a more downward aim. This change of headlight aim gave the crews greater visibility of the track in foggy conditions. According to the crews it worked very well and they would have liked all engines to have their headlights mounted as high as possible.

John Bohon

Phil reminds us that the big oil burning headlights were placed high to clear the smokebox door. They also needed regular attention to refill their oil burners and attention to the wick, cleaning, etc. They were far too large to be attached to the swinging smokebox door, although I am sure someone will find an exception to the rule. They were also likely to be damaged if on the door. Once smaller headlights were available and were electric they needed far less service, just regualr cleaning of the lens and replacement bulbs as needed. They were light enough to mount on brackets that could be attached to the smokebox and flexible cables could still provide power to them, so mechanical departments now had many options for placement. I'm sure books could be written on the variations on every road and why they were made. Some will be due to experience, others just the arbitrary desires of the those in charge. In many cases the reasons will be lost to history, but fun to speculate on.

Just for the record, in the steam era, most steam locomotives were operated with their headlights dark or dim during the daylight hours. The smoke plume and whistle were deemed to be plenty of warning for crossings as well as trespassers.