Semaphore tower and knife: what they have in common

1. Step 1. Semaphore tower — is part of — Optical telegraph. A tower with movable sails.
2. Step 2. Optical telegraph — uses — Lens. Signals were read through telescopes.
3. Step 3. Lens — is part of — Cinématographe. A lens.
4. Step 4. Cinématographe — was inspired by — Sewing machine. Louis Lumière said he came up with the intermittent film feed while watching the fabric feed of a sewing machine.
5. Step 5. Sewing machine — evolved into — Overlocker. A specialized sewing machine.
6. Step 6. Overlocker — has part — Knife. A knife for trimming the edge.

Open Evothings