These handles are made of extremely hard bone, from which we may conclude that they were applied to operations requiring solid tools. Most of them held the flint at one end only; but some were open at both ends, and would serve as handles for two tools at once. Figs. 119 and 120 represent some of these flint tools in bone handles--the plates are taken from those in Boucher de Perthes' work. [Illustration: Fig. 119.--Flint Tool in a Bone Handle.] [Illustration: Fig. 120.--Flint Tool with Bone Handle.] Generally speaking, these handles gave but little trouble to those who made them. They were content with merely breaking the bone across, without even smoothing down the fracture, and then enlarging the medullary hollow which naturally existed; next they roughly squared or rounded the end which was intended to be grasped by the hand. In fig. 121, we delineate one of these bone handles which is much more carefully fashioned; it has been cut off smooth at the open end, and the opposite extremity has been rounded off into a knob, which is ornamented with a design. [Illustration: Fig. 121.--Ornamented Bone Handle.] During the polished-stone epoch, as during that which preceded it, the teeth of certain mammals were used in the way of ornament. But they were not content, as heretofore, with merely perforating them with holes and hanging them in a string round their necks; they were now wrought with considerable care. The teeth of the wild boar were those chiefly selected for this purpose. They were split lengthwise, so as to render them only half their original thickness, and were then polished and perforated with holes in order to string them. In the peat-mosses of the valley of the Somme a number of boars' tusks have been found thus fashioned. The most curious discovery of this kind which has been made, was that of the object of which we give a sketch in fig. 122. It was found in 1834, near Pecquigny (Somme), and is composed of nineteen boars' tusks split into two halves, as we before mentioned, perfectly polished, and perforated at each end with a round hole. Through these holes was passed a string of some tendinous substance, the remains of which were, it is stated, actually to be seen at the time of the discovery. A necklace of this kind must have been of considerable value, as it would have necessitated a large amount of very tedious and delicate work. [Illustration: Fig. 122.--Necklace made of Boars' Tusks, longitudinally divided.] In the peat-bogs near Brussels polished flints have likewise been found, associated with animal bones, and two specimens of the human _humerus_, belonging to two individuals. The peat-bogs of Antwerp, in which were found a human frontal bone, characterised by its great thickness, and its small surface, have also furnished fine specimens of flint knives (fig. 123), which are in no way inferior to the best of those discovered at Grand-Pressigny.