Sliding (la glissade), the best-preserved of the pre-megalithic forms of worship, is characterized by the contact, at times brutish, of a part of the person of the believer with the stone itself. The most typical examples which have been preserved (and as the rites have no doubt generally been carried on in secret, much has escaped the observer) are in relation to love and fecundity.

In the north of Ille-et-Vilaine are a series of large blocks, at times, but not always, worn into cups, which have received the significant name of "Roches Ecriantes" because the young girls, that they may soon be married, climb to the top of them and let themselves slide (in patois ecrier) to the bottom; and some of them, indeed, are to a certain extent polished because of the oft- repeated ceremony, observed by numberless generations, which we are assured has been practised there.

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At Mell( (Ille-et-Vilaine) the " Roche Ecriante " was worn full of basins; on the rock of the same name at Montault, a neighbor- ing parish, inclined at an angle of 45 degrees, there were visible evidences of numberless girls who had there ecriees. After the sliding it was necessary to place on the stone, which, however, no one must see done, a little piece of cloth or ribbon.