One of our finds on moving into an old house was this fine vacuum cleaner.
It's by Eureka and there's a picture of a similar one from the 20s on that page. The company is still operating.
The controls are somewhat limited. I've never actually tried it and there's no plug fitted at the moment anyway.
There are old vacuums for sale on ebay. I know there are some collectors out there. For now it just lives under our stairs.