Skip to content
Innovations archive

Transportation

Railway induction telegraph

1887Cincinnati, OhioGranville T. Woods Verified

The problem

A moving train could not communicate with stations or with other trains; dispatchers were working blind between stops.

The innovation

A system that sent telegraph signals between a moving train and the track-side wires by electromagnetic induction, without physical contact.

How it worked

Coils on the train couple inductively with a conductor running alongside the track, carrying signals across the gap.

Why it mattered

Dispatchers could warn trains of obstructions ahead; collisions fell.

The legacy

A direct ancestor of continuous train-control and modern railway signalling.

You use this today

Contactless communication with moving vehicles — the same principle underlies inductive coupling in transit systems.

Sources

  • US Patent 373,915

    Patent record · United States Patent Office