As I’ve noted before on many an occasion, it never fails to surprise me how disparate events so often seem to occur with a strange sort of synchronicity. No sooner had I started writing my previous blog on A Mishmash of Motors and Stuff than I received an email from about Nautilus Sculptures Based on Logarithmic Gears created by someone who goes by the moniker Rubotix, which led me to this video on YouTube.


Seeing these little rascals in action reminded me of the book 507 Mechanical Movements: Mechanisms and Devices by Henry T. Brown (the original version was published in 1868, but the link given here is to an unabridged printing of the 18th Edition from 1906).

You can also see animations of these bodacious beauties on I remember looking at the Elliptical Spur Gears (Movement 33), which are used where a rotary motion of varying speed is required. These can be used to provide an initial low-speed, high-torque movement that transforms into a high-speed, low torque movement (Movement 38 was also of interest here).

Unfortunately, I don’t have my copy of 507 Movements to hand (I think it’s in the study at home). Speaking of hands — on the one hand, I’d be surprised if Henry Brown had missed a movement; on the other hand, I don’t recall seeing logarithmic gears prior to today.

Whether or not logarithmic gears are to be found in 507 Movements, I have to say that I am well impressed by Rubotix’s Nautilus Sculptures. What say you? Have you seen anything like this before?