What are squints used for?

Answer 1

Squints, or hagioscopes, were holes in walls of churches or chapels so people outside the chapel could see the important parts of the service. They were sometimes used to segregate people, such as lepers, from the congregation while allowing them access to the service. They were also used to conceal people so as not to make them distractions from worship; an example would be a squint for a bell ringer so he would know when to ring the bell.

Answer 2

A squint was a peephole that a king or hulmaner could look down to see what was below