Story & Art: Mac Raboy
Original run: 1955-06-26 to 1955-08-28
Summary: As an African volcano erupts, a mysterious gas released from the crevices that have opened up in the blast spreads a sleeping sickness amongst the local population.
Conducting a uranium survey nearby, Flash and Dale spot engineers from an underworld society breaking into the open to seal the rift, resulting in a close and potentially deadly encounter...
(Source of summary: www.ipcomics.net)
All credits go to "spax".