It has to be printed after 1918 since it says "North Canton, Ohio". Our town used to be called "New Berlin", however, Boss Hoover worked with a local committee to change the name to North Canton just after the WWI since no one was feeling fond of anything German at the time.
The fans were not mounted on a plate and look very strange by todays standards. But they did move air with very little electricity. Good eye on the push button switch. It is a very simple yet effective feature as well as being very well made. These machines were all sand cast not die cast. This made them pricey since they could not manufacture them in larger numbers. They only had 900 employees at the time and they were making leather goods until 1919.
In 1919, Hamilton was established which would date your book to 1918. In 1919 they started selling them in London. This was also the year "It Beats As It Sweeps As It Cleans" became the company's slogan.
Thanks for sharing the instruction booklet. I have never seen one printed like that. It looks to be in very good shape too! Paper for these machines is so hard to find. I hope that you got a good deal on it too!
--Tom