

Windows that opened on early UK trains
What I remember particularly about travelling by train in the 1940s and 1950s was the windows in the doors. They had probably changed little since the early days of the railways, but that of course was outside my personal experience.
'Health and safety regulations' had not been dreamed up, and the windows in the train doors opened so that passengers could lean out. This they did, particularly when waving goodbye to people seeing them off.

Open window in a typical 1940s train door.* The green walls were due to the whole carriage being the dining car. Normal compartments had the same windows and non-descript colour walls.

Waving goodbye through an open train window in the 1940s
How train windows opened and closed
Windows could be raised and lowered with a leather strap and held in position by locking one of the holes in the strap over a metal stud. The arrangement is shown in the first of the above photos.
The danger of leaning out of the window
There were notices pointing out that it was dangerous to lean out of the window while the train was moving, but it didn't stop anyone. We all seemed to think that we would spot a train coming in the opposite direction or a bridge approaching and dodge back inside quickly. This normally worked, but there were cases of people being decapitated when leaning out of train windows.
The enjoyment of leaning out of the window
Leaning out of a train window of a moving train was a particularly enjoyable experience for children: to feel the wind rushing into one's face and through one's hair and to see the engine belching out smoke as the train rounded a bend.
The annoyance of leaning out of the window
A particular problem with leaning out of a train window was the smoke from the engine. It was sooty from the partly burnt coal: it got into eyes and made faces black, even if the leaning out was only for a few moments. There was also the occasional spark which was painful.

The stream of sooty smoke from the engine of a steam train.* As the train rounded a bend, it was fascinating to watch it from an open window, snaking through the countryside.
So children were encouraged to 'stay inside' when out visiting; otherwise there was a quick lick and a promise from mother's handkerchief at the end of the journey.
Passengers' arguments
Irrespective of whether anyone was leaning out of the window, it was not always easy to get agreement among the passengers about how far the window should be pulled down. It could be too draughty and dirty for passengers sitting facing the direction of travel, but not for the passengers facing them.
Mesh protection against shattering in bomb blast
In the first half of the 1940s I suppose there could have been mesh stuck onto the train windows against the bomb blasts of World War Two, but perhaps this was only for trains in cities, rather than those crossing in countryside in daylight. I only remember the mesh for the London Underground. Do you know?
Either way, any mesh was probably removed as soon as possible after the war ended, because it was so unpleasant being unable to see out of the windows.
If you can add anything to this page or provide a photo, I would be pleased if you would contact me.
Text and images are copyright
*Photographed by the webmaster with acknowledgements to the Steam Museum at Swindon