“The sheep, cattle and horses of the townland graze together, the species being separate. A tenant can only keep stock conformably to his share in the soil. He is however at liberty to regulate the proportions of the different kinds, provided that his total stock does not exceed his total grazing rights. He can keep a greater number of one species and a corresponding smaller number of another. Or he can keep a greater number of the young, and a corresponding less number of the old of the same species, or the reverse. About Whitsuntide, when the young braird appears, the people remove their sheep and cattle to the grazing ground behind the arable land. This is called clearing the townland. The tenants bring forward their stock (Leibhidh) and a souming (Sumachadh) is made. The _Leibhidh_ is the tenant’s stock, the _Sumachadh_ the number he is entitled to graze in common with his neighbours. Should the tenant have a croft, he is probably able to graze some extra stock thereon, though this is demurred to by his neighbours. Each ‘penny’ of arable lands has grazing rights of so many soums. Neither, however, is the extent of land in the penny, nor the number of animals in the soum uniformly the same.” A soum consists of a cow and her progeny; in some places the cow and her calf only: in some a cow, her calf, her one-year-old progeny (called a _stirk_) and her two-year-old _quey_; in other places again, the cow, calf, stirk, quey and a three-year-old heifer. At four years old the heifer becomes a cow, and so originates a fresh soum. In making souming calculations, it is assumed that one cow is equal to two queys or to four stirks or to eight calves, or to one heifer and one stirk. Also one cow is equal to eight sheep, or to twelve hoggs (one-year-old sheep) or to sixteen lambs or to sixteen geese. One mature horse is equal to two cows; also to eight foals, or to four one-year-old colts or fillies, or to two two-year-olds, or to one three-year-old and one colt or filly. The cow is entitled to her calf; and if one tenant has two cows without calves they are entitled to take one stirk instead. Those tenants who are found at the souming to have overstock must either buy grazing from a tenant who has understock or may be allowed by the community to let the overstock remain on the grass till he can dispose of it. In that case payment must be made, according to a recognised code, into a common fund which is used to buy bulls or tups or for some other common purpose. The souming is amended at Lammas, and again at Hallowtide. In Lewis and Harris similar arrangements with regard to stock obtain among the _crofters_, the amount of stock allowed to each crofter being regulated according to the rent paid.