Henry Yelf's typwriters

Here's a little bit of Yelf-ian that appeared on ebay recently. It's a promotional postcard advertising the virtues of a Monarch typewriter, but the bit that's of interest to Yelfs is the small stamp in the bottom right hand corner. This was obviously added in Henry Yelf's shop in Portsmouth      

I'm by no means a postcard collector, but I was certainly interested in this one - until it went up to about £10, at which point I decided I'd make do with a photo!