I couple of years back I discovered an article about Mr Kitchingman and his flea circuses from an Andy Clarke of The Foxearth and District Local History Society
A followup of this led to:
- The World of Wonders, A Record of Things Wonderful in Nature, Science and Art Published 1868
- En cherchant la petite bête By Albert Fournier
- The Curious World of Frank Buckland
The World of Wonders appears to have a fabulous article with pictures on page 37 about Professor Kitchingman and states "Professor Kitchingman, an enterprising entomologist recident near Brussels" and reference to what appears to be a tightrope act. The British Library has a copy of this so hopefully it's not one of those items that they are moving to Boston Spa.
Albert Fournier's book also provides an interesting lead in the form of an new function in the google books search, the subject search. For example I could search for subject:"Fleas in literature".
Looking up "Frank Buckland", I discovered that he had written a series of books called "Curiosities of Natural History" which seems like a good lead too