For most of my model railroading career I’ve seen models and prototype photos depicting water barrels on wood trestles and at the peaks of roofs. Most of the time these appear in the slide valve era. For a long time I had no clue what they were for, then it occurred to me that they might be a crude fire suppression system. Am I right? If not, what is the right answer?
If they were for fire suppression, were they effective?
Yes, fire suppression.
They were effective in stopping small fires from becoming large fires, back in the days when steam engines spewed cinders and cast-iron brake shoes shed sparks, and there were trackmen walking the track with a joint bar wrench, section gangs with small territories, and signal maintainers putt-putting down their territory every day to charge batteries.
RWM
Way back when, some buildings had a system where there was a water tank on the roof, if there was a fire you could somehow (long chain?? lever system??) open the bottom of the tank, and the water would spill out on the roof. Usefull if the roof exterior is catching fire (like sparks being blown on it from a neighboring building on fire) but not too much help if the building interior was burning.