Roof vents

What is the name for those pumpkin-shaped (bulbous) things, with slitted sides, that whirl on top of roofs? They seem to be turned by wind currents. I always called them “pumpkins,” but I don’t know that that’s their right name (or ever could be).

I think their real name is “wind turbines.”

However, in one of my favorite childhood books (one of the many that were gifts from a librarian aunt), Chimney-Top Lane, a similar item was called a chimney monkey – and that’s what I’ve called them ever since, even after I learned the right name a few years ago. I even have Mr. S. calling them that.

They are called “turbine vents.”

My garden and rural supply catalog lists them as Pinwheel Vane Vents.

Another name for them is “Whirly Birds”.