Black Painted Round Fluted Mirror Frame With Convex Mirror, English 20th Century.

Further readings and sources:

1. These were sometimes called a butler’s mirror, hung at the opposite end of the dinning room from where the butler would stand during meals so that he could monitor the table while looking straight ahead from his post. ↩
2. Also referred to as a bull’s-eye mirror. In the 19th Century, a circular convex mirror would also be referred to as a girandole. ↩