this is not what you think even the derailment of trains is damaging to the train and tracks and possibly a criminal act there are situations where trains are intentionally derailed for good reasons for example when the track is under maintenance but the train is still moving that way which would collide with the equipment and personnel this little device known as a derailleur does just that it can be quickly installed on the track and is assigned to show that it's in place and engaged derailers are usually used for derailment at slower speeds but derailers have been
around for a long time as can be seen in this footage from the early 1910s there's also a little light in the middle so it's more visible especially at night but don't worry because derailed trains can be re-railed by placing blocks next to the track and rolling the wheels over and back onto the rails
