Can you find the ghost in this 1900 photo?

If you're one of those who loves haunting stories, photos and videos that are supposed to show ghosts as well as mysteries involving otherworldly stuff, this is for you!

A photograph showing 15 young people working in a factory in Belfast, the capital of Northern Ireland, is rolling around. So far, all normal: another interesting historical record for today.

But someone noticed that there was something strange about the portrait. Take note: