Arthur W J G. Ord-Hume. Perpetual Motion: The History of an Obsession. George Allen and Unwin, 1977.
In the course of his researches on musical-boxes and antique automata, the author, Ord-Hume, came across many fascinating references to perpetual motion machines, as theoretical concepts and as allegedly working devices. The fascination of such a machine is obvious, it is the lure of something for nothing; which we have been told by endless generations of puritanical elders-and-betters is not only impossible, but also bad for you! Who could resist such a challenge?
Practically no-one, it would seem, and this book describes a parade of ignorance, misguided ingenuity, crack-pottery, and downright deviousness. At first perpetual motion was sought as a practical aid to such operations as milling. A water-wheel, besides driving a mill, might also pump enough water back uphill to flow down again and drive the wheel. The book features many charming old woodcuts which show just how this was to be done. Unbelievably a saw-mill was built to utilise this theory in the USA as late as the 1870s. It didn't flourish! later, perhaps in keeping with the dilettantism of eighteenth century science, the proposals for perpetual motion devices become mere toys, trundling or bobbing along forever, performing no useful function.
Besides the genuine cranks, there were the hoaxers too. For some reason the city of Philadelphia seemed to be a centre for them. Like the. tricksters of our own age, they were usually able to find some gullible scientist or learned institution to back their curious claims. In an interesting comparison, the author says: “I found several mysterious devices which, rather like that small percentage of Unidentified Flying Object sightings, cannot be explained away.
Amongst the self powered mills, 'the over-balanced’ wheels and intricate devices involving soggy sponges, there is a clock that worked for 150 years, and only stopped when the building it was installed in was demolished. There are electric pendulums which seem set to swing their way, ringing a little bell, for five hundred years or so. Perhaps not perpetual motion, but as Ord-Hume comments "Nevertheless, I feel that the creation of something which may continue to show movement for half a millennium, however it achieves that, is something deserving of more than passing mention."
The penultimate chapter looks at the perpetual mostion possibilities of the nuclear age. Maybe, it concludes, we have the perpetual motion machine, the something-for-nothing machine in the form of the fast breeder nuclear reactor which produces more fuel than it uses. And sadly, thay may prove to be all-too perpetual. -- John Rimmer, from Magonia New Series 7, Summer 1977.