The Hemlock Stone
From Bypaths of Nottinghamshire History
John Potter Briscoe (1848-1926), historian and Nottingham librarian, included a passage on The Hemlock Stone in his 1905 book "Bypaths of Nottinghamshire History"
The two pictures he refers to in the text are shown here:
"An old person"
J P Briscoe
He writes: "The two half-tone illustrations are from our own "snap-shots" which were taken to illustrate the curious profiles of a bird and an old person as they struck us on the occasion of one of these visits to Bramcote."
Here is the rest of the article:
“THE Hemlock Stone" at Bramcote is one of the enigmas of the County, not only to the rank and file of its inhabitants but to the generally well-informed portion of our community. Much has been written about it, more has been spoken, but the puzzle has not been solved in a general sense. In the first series of our “Old Nottinghamshire" we quoted the opinions of poets and antiquaries, but it is, we are convinced, to the geologist and the chemist that we must look for the answer to the oft asked question, "What is the Hemlock Stone?"
Prof. Frank Clowes, D.Sc., in a contribution for one of our magazines, wrote as follows on the subject, based upon a paper contributed to the Aberdeen meeting of the British Association. "At the spot in question the sandstone appears as two hills, known as Stapleford and Bramcote Hills, and in the intervening valley there is a pillar of rock called The Hemlock Stone. The hills are conical in shape. The Hemlock Stone is a mushroom-shaped pillar somet wenty feet in height. Professor Blake visited the spot with me some short time since, and we procured specimens of the sandstone from different levels of the hills and of The Hemlock Stone…The whole of the sandstone specimens from the two hills already mentioned contain barium sulphate in varying proportions…whilst some of the lower beds also contain calcium carbonate. Those geologists who collected their specimens from the lower portions of the Hemlock Stone would undoubtedly detect a carbonate by the ordinary test with an acid, and would, therefore,consider the sandstone to be calcareous; but if they had procured samples of the mushroom shaped top of the stone they would have found no carbonate, and would have failed to detect by the acid test the true cementing material, which is Barium Sulphate. It seems probable that the protective cap of the pillar owes its comparative permanence against weathering action to the presence of a very large quantity of this almost insoluble sulphate…
In one bed which caps the Bramcote Hill the barium sulphate is present in little isolated patches about the size of a hazel-nut, and the weathering of this sandstone accordingly yields little pebble-like masses of sand held together by the sulphate; this bed is accordingly usually described by the geologist as a pebble bed, although this name is not strictly appropriate.
I have attempted to detect some evidence of the way in which this barium sulphate has been introduced into the original sand-bed. It may possibly have been deposited together with the sand, but if this is its origin it has certainly undergone physical change, since it exists now in a firm, compact, and crystalline condition. It seems certain, therefore, that it has either been originally deposited from aqueous solution, or has been rendered crystalline by the slow percolation of a solvent liquid through the sedimentary deposit, or else it has been formed by the action of water containing calcium sulphate percolating through sandstone originally cemented with barium carbonate. This double decomposition between calcium sulphate and barium carbonate has been artificially carried out by Bischof, and the presence of calcium carbonate together with barium sulphate in some of the beds in question may indicate such an origin. With regard to the possibility of barium sulphate being deposited from solution, or being rendered crystalline by a solvent, it must be remembered that barium sulphate stalactites exist: the origin of these stalaclites is undoubtedly similar to that of ordinary calcium carbonate stalactites, and one which I have recently examined consists wholly of the sulphate. I have also received sand-pebbles bound together with large and well-formed crystals of barium sulphate; and that such crystals have been deposited from solution and not from fusion has been demonstrated by Bischof almost beyond doubt."
Further information about The Hemlock Stone can be found on The Stapleford Website.
There's a poem about the Stone, quoted by Briscoe in his article, here.