Slang in an early Wodehouse story

I've moved house recently, and one of the things I had to deal with was getting rid of a number of books I've had for a long time. This took place over the last two or three years, with the result that I've now got less than half the books I used to have. 

That's still quite a few books, but now they fit on two bookcases instead of four or five. And we'd already culled our books a couple of times before the most recent slashing and burning. The house must have been straining under the weight of a...