Carolyn: "Ada has some odd sundial references, but of a mathematical nature. I think the word is gnomon, and I have wondered of the L-disaster wasn't somehow related to it."

Jansy: We have Kinbote's information about Shade's short poem "The Nature of Electricity," which John Shade had sent to the New York magazine The Beau and the Butterfly,"...:
"The dead, the gentle dead — who knows? —In tungsten filaments abide,.../ And maybe Shakespeare floods a whole/Town with innumerable lights,/And Shelley’s incandescent soul/ Lures the pale moths of starless nights...", before he added:

 "Science tells us, by the way, that the Earth would not merely fall apart, but vanish like a ghost, if Electricity were suddenly removed from the world."

I've found references to something called "cartesian devil" (a kind of barometer?) in at least two works by VN and you once bought one and sent the list a picture: how about posting your conclusion, correction to the instrument's name and image again?