Starch filler and optical telegraph: what they have in common

1. Step 1. Starch filler — is part of — Tablet (medicine). Starch or lactose.
2. Step 2. Tablet (medicine) — uses — Hydraulic press. Tablets are pressed.
3. Step 3. Hydraulic press — is made of — Cast iron. Bramah’s press is cast iron.
4. Step 4. Cast iron — is material for — Railway semaphore. On a cast-iron mast.
5. Step 5. Railway semaphore — evolved from — Optical telegraph. The semaphore idea.

Open Evothings