A similar entry appears in the Wheel of Time Companion confirming the information available in the main story arc.
Author: Atarah al'Norahn
Ryn Anhara is a man who stays at Cairhien Academy.
The invention that he is working on involves trapping lightning in big jars, though Idrien does not think even Ryn himself knows why he is doing it. When Idrien first tells Rand about the invention, he mistakes her to mean that Ryn can channel, but Idrien hurries to assure him that he cannot. The invention is a thing of wires, wheels, big clay jars and the Light knows what, according to Idrien. She says that she once saw a rat jump on top of one of the jars, on the metal rods sticking out of the top, and it certainly looked struck by lightning. Rand thinks to himself that catching lightning in jars is beyond his ability to imagine.
(Reference: Winter's Heart, Prologue)