I opened the article without a clue about what they were. Within my first 5-10 s on it I knew what they were. Literally right below the title: > bricks that p

I opened the article without a clue about what they were. Within my first 5-10 s on it I knew what they were. Literally right below the title: > bricks that provide nesting for swifts and other endangered birds And a picture.