Captain Sturmy descended into the pit on July 2, 1669. Having roped down from an old lead mine, he and a miner companion descended using 25 fathoms () of rope. They found a large chamber which they illuminated with candles. Exploring further they found an underground river 20 fathoms wide. Seeing a passage above them, they had a ladder lowered which they used to ascend into the passage. Here they found what they thought was a rich mine "an abundance of strange places, the flooring being a kind of a white stone, enamelled with lead-ore, and the pendant rocks were glazed with saltpetre, which distilled upon them from above, and which time had petrified." After a few hours they ascended to the surface, but the unfortunate Captain Sturmy suffered from a severe headache for four days, developed a fever and died. This gave the hole a bad reputation and for a long time, nobody was willing to explore it further.