A snippet from the latest edition of Current Archaeology:
According to Freud, horses symbolise the sexual drive, while Jung said they represented fertility (but then, those two had a habit of seeing sex in everything.) Could any of this explain the deposition of horse skulls and leg bones in 16th- to 18th-century lime kilns? No sooner had Current Archaeology 213 published an article featuring just such a ritual deposit, saying “we know of no parallels”, than along come another three examples, all found by the Ingleborough Archaeology Group (IAG) in the Yorkshire Dales.
“In two of the kilns, at Feizor and at Newby Core near Clapham, we found nearly identical sets of bones – a skull, at least one large leg bone, one shoulder bone, and a couple of vertebrae,” said IAG Chairman, David Johnsone, adding that “They had all been stacked in a pile very neatly. A third, near Kilnsey, just had a horse’s skull in it.”
The practice of using animal bones in closure deposits and building foundations goes back to the Neolithic. Most archaeologists interpret these as an attempt to appease the spirits of the earth or give something back in return for that they have taken from the ground. Certainly these seems to be a way of thinking about the balance between giving and taking from nature that our more rapacious age has entirely forgotten.
Reference: Catling, C. 2008. Horses in lime kilns. Current Archaeology 215: 10