The photograph used on the front cover of the October 2020 issue of the journal, and its accompanying article,1 showing its author Thomas B. Greenslade seated in the apparatus museum wing of his house in Gambier, Ohio, reminded me very much of the personal “cabinet of curiosities” of old. Though Greenslade's collection is far more orderly and organised than a traditional cabinet of curiosities, it stands as a wonderful collection of notable physics objects spared the ignominious fate of being dumped simply for being old. Who as a teacher of physics has not chanced across an old piece of equipment buried out of sight in their back room equipment store and wondered what it is, how does it work, and could it still be used?

In this connection, the story of the little known English amateur mathematician and astronomer Henry Perigal (1808–1898) is worth telling. He is a curious character from the second half of the nineteenth century. Labelled by the English mathematician Augustus de Morgan as a “paradoxer” for the strongly heterodox views he held regarding the lack of rotation of the moon about its axis as it orbited the earth,2 Perigal is perhaps best remembered today for his elegant dissection proof he gave for Pythagoras' theorem.3 In his own day, Perigal was largely recognised for his skill as an ornamental lathe turner and the beautiful and intricate curves he produced that were the result of various compound circular motions. As your archetypal Victorian scientific amateur his hobbies and interests could be described as being broadly geometric. Living to a great age, by his latter years his home had turned into his own private cabinet of curiosities. As one fortunate visitor recalled:4 

What a scene it was, that labyrinth of strange relics of science, the marvels of bow-pen lacework, the instruments covered up to keep the dust off, the Philosopher's simple couch in the corner all in view of these quaint things, and the Philosopher himself indefatigably squaring the circle or trisecting an angle, or proving that the world is all wrong about the moon. I don't know what it was that he was at then, but it was all like a leaf out of a book, wonderful and almost incredible. And the birthday album laid there with the autographs of all the high priests of science. What has become of it I wonder, and of the bow-pen work, and all the odd things strewn about in such profusion? I must write an account of it someday. It was exquisite.

It must have been a magical place to visit that has now all been lost. Here's hoping Greenslade's cabinet of curiosities is preserved for future generations to admire and enjoy.

Thomas B.
, “
Adventures with historical physics apparatus
Am. J. Phys.
de Morgan
A Budget of Paradoxes
Longmans, Green, and Co.
), pp.
Greg N.
Dissections: Plane and Fancy
Cambridge U. P
), pp.
Museum of the History of Science (UK), Manuscript Gabb 11, folio 56.