I was fascinated by some of the crazy things people tried to get working that were discussed on that show. Things like keeping a pair of dogs, wounded by the same knife, as a way to synchronize time. As if they were some kind of quantum entangled particles.

Edit: Found it!

The powder was also applied to solve the longitude problem in the suggestion of an anonymous pamphlet of 1687 entitled Curious Enquiries. The pamphlet theorised that a wounded dog could be put aboard a ship, with the knife used to injure the dog left in the trust of a timekeeper on shore, who would then dip said knife into the powder at a predetermined time and cause the creature to yelp, thus giving the captain of the ship an accurate knowledge of the time.