Study of Beelzebub's Tales




41 The Bokharian Dervish Hadji-Asvatz-Troov


“‘This siren was invented two centuries ago by a certain learned physician named Zehbek and it was so to say perfected in the middle of the last century, by a certain Cagniard-de-la-Tour.


“‘Unfortunately for the Europeans, neither the first inventor nor the perfecter of that siren knew that sound can be obtained not only from the action of genuine vibrations but also from the simple flow of air; and as this siren of theirs sounds only from the flow of air and not at all from natural vibrations, therefore the determination of the exact number of vibrations by the indications of that siren is out of the question….

“‘And, that sound can be produced from two causes, namely, from natural world-vibrations themselves and simply from the flow of air, is a very satisfying and interesting fact, and I shall now demonstrate it to you practically.’