[TorryJens]

I don't really see a need to have the alarm chain at all. If there is an emergency and you pull the chain to let the train stop in the middle of a jungle what is being gained? Instead an intercom should be installed in every carriage where by pressing a button the individual can talk by giving details (including his name and the carriage number--so that he can be identified). If there is a medical emergency, the engineer (driver) can announce through the intercom for help from any doctor in the train who can then be directed to the particular carriage in question. I hope the carriages are interconnected. If no immediate help is available the engineer can stop at the next station which may not be very far and get help there for the emergency. Even a fire can still be first communicated to the driver before the train can be stopped.