Narrow stone passages and greenhouse: what they have in common

1. Step 1. Narrow stone passages — is part of — Egyptian pyramid. Passages inside the mass.
2. Step 2. Egyptian pyramid — is made of — Stone. The pyramids are built of limestone and granite blocks.
3. Step 3. Stone — is material for — Gothic cathedral. Cathedrals are built of dressed stone.
4. Step 4. Gothic cathedral — has part — Window glass. Stained glass.
5. Step 5. Window glass — is part of — Greenhouse. It lets light in and holds heat.

Open Evothings