Sighting vanes and aerosol can: what they have in common

1. Step 1. Sighting vanes — is part of — Quadrant. A sight for the celestial body.
2. Step 2. Quadrant — is made of — Bronze. Quadrants are bronze or wooden.
3. Step 3. Bronze — is material for — Valve. Ancient taps and valves were bronze.
4. Step 4. Valve — is part of — Aerosol can. A valve.

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