Warning Flares and Torpedoes

Back in the steam era, before radios, warnings were given to the engineer by the use of flares or Torpedoes. Torpedoes were placed on the rails, and made a loud bang when run over. They were loud enough so the engineer could hear it over the noise of the engine.
Does anyone know if these items would be available? If not, is there anyone that would be interested in making some. I certainly do not have the skills to do it.
Thanks much.
Does anyone know if these items would be available? If not, is there anyone that would be interested in making some. I certainly do not have the skills to do it.
Thanks much.