Steam locomotive and sonar: what they have in common
- Step 1. Steam locomotive — evolved into — Diesel locomotive. It replaced the steam locomotive.
- Step 2. Diesel locomotive — has part — Diesel engine. The diesel turns a generator.
- Step 3. Diesel engine — is part of — Submarine. Diesel-electric submarines.
- Step 4. Submarine — has part — Sonar. Underwater acoustics.