The backmark is “improved quality”, a generic branding, probably British.
The “mole” is for “moleskin”, a heavy cotton fabric noted for its durability and softness, so this would be a trouser button from moleskin trousers.
The sarcastic paragraph below seems to be ridiculing men overly influenced by advertising …
Victoria mole trousers were advertised from 1859-1870.
In advertising from the 1880s-1913 there were listed Victoria cord trousers, Victoria twist trousers, and Victoria tweed trousers and suits. I guess that ‘Victoria’ was a brand and/or style of menswear.