William Pengelly was one of the most celebrated geologists of the nineteenth century. He was born in 1812 in East Looe on the south Cornwall coast,  but moved to Torquay in Devon at the age of 24. Self-taught, he ran a school, and became interested in mathematics and geology which led to him playing a leading role in the formation of the Torquay Natural History Society (of which he was secretary for almost 40 years) and the Devonshire Association (of which he was elected President).

William Pengelly developed a specialist interest in the geology of Devon, and was particularly interested in the caves in the county. He conducted excavations in Windmill Hill Cave at Brixham, of deposits at Bovey Tracey and at Kents Cavern at Torquay (which was to occupy him for 15 years), and this work made a major contribution to the development of modern thinking about geology and pre-history. His work on fossil remains in Devon was particularly important as part of the development of 19th century understanding of evolution of which the publication of Origin of Species by Charles Darwin was a part.

Pengelly was a meticulous scientist and wrote extensively about his work. He had an international reputation, travelled widely in Britain lecturing about his work in Devon, and was a key figure in the work of the British Association for the Advancement of Science. He was elected as a member of the Geological Society and, in 1863, a Fellow of the Royal Society.

Although William Pengelly did not conduct excavations at Buckfastleigh he is known to have visited Bakers Pit Cave a few years after it was discovered by quarrying in 1847. Had quarrying at that time revealed the deposits in Joint Mitnor Cave, he would undoubtedly have been in the forefront of the excavation of what is now one of the most important sites of its kind in Britain.