1874

Spring
Matthew and James Hardy arrive in London, the latest stop on their world tour.  They are intrigued by rumors of vast networks of underground tunnels and caverns below the surface streets of the city.

June
The Hardy brothers mount their first expedition into the underground tunnels and caverns beneath the city of London with help and financing from Berkley Vanderzee and Geoffrey Hawkins.

August
On their second subterranean expedition beneath the city of London, Matthew and James Hardy discover a plasma-type gas that will eventually come to be known as æther.  They present their samples to Berkley Vanderzee and Geoffrey Hawkins, who begin research and experimentation on the substance.