Some curved knives of polished slate, about 5 inches long, notched at the base as if for suspension by means of a string, have been found in Norway. Small blades of chipped flint with a neck for the same purpose are not uncommon in Japan, and occur more rarely in Russia.[1624] In the Greenwell Collection is preserved a curved knife of slate sharpened on the concave side, found in Antrim. Curved knives of flint, as well as some of the crescent shape, have been found in Volhynia.[1625] I have seen flint knives in outline very like Fig. 240 in the museums at Cracow, Moscow, and Kiev. Some are highly polished by friction and may have served as sickles. It is difficult to assign any definite use to the British form of knife, but as the curvature is evidently intentional, and as probably it was more difficult to chip out such curved blades than it would have been to make them straight, there must have been some advantage resulting from the form. As both edges of the blade are sharp, it is hard to say whether the convex or concave edge was the principal object. But inasmuch as the convex edge might more readily be obtained, and that twice over, in a leaf-shaped blade, it appears that the concave edge was the desideratum. The blunting of the edges at the butt-end suggests the probability of the instruments having been held immediately in the hand without the intervention of any form of haft; and the view of the concave edge being the principal one is supported by the circumstance that in the short knife from Ganton Wold, already mentioned, a considerable portion of the crust of the round-ended nodule of flint from which it was made is left along the convex side at the butt-end, while on the opposite side the edge extends the whole length, so that it cannot be comfortably held in the hand except with that edge outwards from the palm. It seems, indeed, adapted for holding in the hand and cutting towards rather than from the operator; and looking at the form universally adopted for reaping instruments, which seem to require a concave edge, so as to gather within them all the stalks that have to be cut, I am inclined to think that these curved flint knives may not impossibly have supplied the place of sickles or reaping hooks, whether for cutting grass to serve as provender or bedding, or for removing the ears of corn from the straw. We know that amongst the inhabitants of the Swiss Lake-dwellings some who were unacquainted with the use of metals had already several domesticated animals, and cultivated more than one kind of cereal, and it is not unfair to infer that the same was the case in Britain. It has already been suggested that some serrated flint flakes may have served for the armature of another form of sickle, like that in use in Egypt at an early period.