"It proved that he had correctly solved one more than I had. This point settled, I said 'Good-bye.'
"'Good-bye. Do come again as soon as you can. The farmers know nothing whatever about Trigonometry.'
"We parted at the rectory door, and have never met since; nor shall we ever do so more, as his decease occurred several years ago. During my long walk to Wellington my mind was chiefly occupied with the mental isolation of a rural clergyman."
In 1851 he lost his wife, and some years after both his children by her.
In 1853 he married a Lydia Spriggs, a Quakeress.
William Pengelly's scientific explorations may be divided under three heads. The first was his minute and accurate examination of the deposits that form Bovey Heathfield, where there are layers of clay, sand, and lignite. He was able to extract numerous fossil plants, and thereby to determine the approximate age of the beds.
Next he took up the exploration of ossiferous caves; and he began this work with that of Brixham, in Windmill Hill.
The floor of this cavern was excavated in successive stages or layers, starting from the entrance. Bones were found in the stalagmite and in the first, third, and fourth beds, and worked flints in the third and fourth beds only; but where the third bed filled the cavern up to the rock, its upper portion contained neither bones nor flints. The bones were those of the mammoth, the rhinoceros, the urus, hyæna, cave lion and cave bear, etc.
But by far the most laborious scientific undertaking of Pengelly's life was the exploration of Kent's Cavern, near Torquay. This cave was known as far back as 1824, when a Mr. Northmore, of Cleve, near Exeter, made a superficial examination of it to ascertain whether it had been a temple of Mithras, and quite satisfied himself on this point. He was followed by Sir W. C. Trevelyan and by the Rev. J. MacEnery. But it was not till 1865 that a complete, scientific, and exhaustive exploration was undertaken by the British Association, which made a grant of £100 for the purpose. Mr. Pengelly was appointed secretary and reporter to the committee for the examination of the cave and its deposits.
It was found that the floor of the cave exhibited the following succession: (1) Blocks of limestone sometimes large, clearly fallen from the roof. (2) A layer of black mould ranging from a few inches to upwards of a foot in depth. (3) Beneath this came a floor of granular stalagmite, about a foot in thickness, formed by the drip of water from the roof. (4) A red loam containing a number of limestone fragments. (5) A breccia of angular fragments of limestone and pebbles and sandstone embedded in a reddish sandy calcareous paste.