These books are a wonderful read, cover to cover you will find contraptions and ideas for solving all sorts of problems of every day life.
Many of them may have been practical years ago but are now jaw dropingly weird, but they will still make you knock away the cobwebs in your brain and appreciate the cleverness of these books.
Volume one is available from Project Gutenberg as a free download (its over 500 pages long!) as it’s now out of print but volume three you can buy from Lindsay’s Technical Books (a goldmine of almost forgotten information can be found there!). It would be worth looking for volume one on eBay just because having a nicely bound book is a heck of a lot better than a stack of papers held together with binder clips.
The Boy Mechanic: Volume 1 by Popular Mechanics
The Boy Mechanic: Volume 3 from Lindsay Books