| In the very bottom you can see what looks like a mop head, that's where oil is put and it keeps the axle lubricated as it turns. Car inspectors used to carry a hook to lift the lid as you see here and an oil can to replenish the supply as needed. If these ran dry, we would end up with a "hot box". Smoke, fire and then usually a cut journal. This would result in derailments, often of catastrophic proportions. All crew members were to check their train in every curve for signs of a hot box. |