On a swampy common called Saltonstall-moor, in Warley, is a fine large altar, called by the country people the Rocking Stone, the height of which on the West side, is about three yards and an half. It is a huge piece of rock, with rock basins cut upon it, one end of which rests on several stones, between two of which is a pebble of a different grit, seemingly put there for a support, and so placed that it could not possibly be taken out without breaking, or removing the rocks; these in all probability have been laid together by art. The stone in question, from the form and position of it, could never be a rocking stone, though it has always been distinguished by that name: the true rocking stone lies at a short distance from it, thrown from its centre. The other part of this stone is laid upon a kind of pedestal, broad at the bottom, but narrow in the middle; and round this pedestal is a passage, which from every appearance, seems to have been formed by art, but for what purpose is uncertain.
He conjectures that people passing through such passages would have acquired some kind of holiness, or knowledge, or that it was a sort of rite of passage. That sort of thing.
At the distance of about half a mile from this huge rock are the remains of a Carne, formed of loose stones, which for centuries has been called by the country people, Sleepy Low. Several broken fragments of rock are strewed over the moor, these are rendered more remarkable from the fact that the common is one vast morass.
From 'A concise history of the parish and vicarage of Halifax' by John Crabtree (1836).