The contents of this book are borrowed from a very old book (printed in the 19th century I think), and thus the contraptions and devices that are shown therein have been eclipsed by modernizations of the same things. The sheer ingenuity of these devices gives the book its worth in the present day. Where I probably wouldn't build many of the devices exactly as they would, the illustrations and explanations (problem/solution format) gave me ideas for new and better devices. This book is excellent for the inventor, and perhaps even the occasional historian/nostalgia-enthusiast. Well worth its price (I recieved it as a Christmas gift!)
These books (there are two others in this series, I think - "Farm Appliances" and "Fences") are truly wonderful. I have lived my whole life on a farm and I have seen some of the things shown in these books, but to see the whole range of rural inventions in one place is an overwhelming testimony of the ingenuity and brilliance of our forefathers. I also think the introductions by Denis Boyles are the funniest things I've read in a long time.