Starter motor and syringe: what they have in common

1. Step 1. Starter motor — evolved from — Crank. It replaced the starting crank.
2. Step 2. Crank — is part of — Sewing machine. A crank turns rotation into the stroke of the needle.
3. Step 3. Sewing machine — has part — Needle. A needle with the eye near its point.
4. Step 4. Needle — is part of — Syringe. A hollow needle.

Open Evothings