Shomescope

Clever caption involving time travel and historical references coming soon, and now for something completely different.

I was about to retire to the parlour to enjoy a bit of evening entertainment along with my guests, that shall remain unnamed, when I caught a glimpse of my reflection in the ever mysterious Shomescope. I was instantly shaken out of my state of complacency and began to puzzle over the complexities of traveling in time and its implications on the fragilities of human mind. When was I?