To conclude, we must repeat that trepanation is not really a dangerous operation, and the reason it is nearly always followed by the death of the subject in our own time is because it is never attempted except in desperate cases, and the fatal result is really caused by the cerebral disease, on account of which the operation was performed. History tells us of its practice in very ancient times; Hippocrates speaks of it as often resorted to by Greek physicians. It is performed in the present day by the Negritos of Papua and the natives of Australia and of some of the South Sea Islands, where it is considered efficacious in many maladies. We also find it practised by the rough miners of Cornwall and the wild mountaineers of Montenegro.39 An army doctor who travelled in Montenegro a few years ago said that it was no rare thing to meet men who had been subjected to trepanation seven, eight, or even nine times. It is an interesting question, though we must not enter into it here, whether many races could stand such a number of operations as this. The only instance we know in the present day of trepanation practised as a religious rite, is met with among the Kabyles, who are established at the foot of Mount Aurès on the south of the Atlas. The operation is performed among them by the _thébibe_, one of their priests, by the aid of a simple gimlet which he turns rapidly round between his fingers. Among the Kabyles are men who have submitted to an operation of this kind several times. We have now passed in review the weapons of prehistoric peoples, the wounds they caused, and the modes of healing them known to our ancestors; we have still to study the modes of defence resorted to by them in face of the many dangers by which they were surrounded; but the importance of this subject is such as to deserve separate consideration. 1 Foureau, _Bul. Soc. Géog_., June 1, 1883. 2 Munck has just discovered a similar station at Oburg (Hainault), where similar implements, produced by similar processes as those at Spiennes, were discovered. 3 Briart, Cornet, and Houzeau: _Rapport sur les découvertes faites à Spiennes en 1867_. Malise: _Bul. Acad. royale de Belgique_. 4 _Journal, Ethnological Society_, 1818, p. 419. 5 _Académie des Sciences_, Nov., 1883. _Mat_. Jan., 1884. Nature, June 18, 1887. 6 _Nature_, June 16, 1887. 7 Heilbig: “Osservazioni sopra il Commercio del l’Ambra” (_Acad. dei Lincei_). We must not confound the yellow amber of the Baltic with the red amber found in Italy, in the mountains of Lebanon, and even in some lignites in the south of France. Sadowski: “Le Commerce de l’Ambre chez les Anciens.” 8 Nephrite is found in Turkestan, in Siberia, and in New Zealand. Deposits of jadeite are known in Burmah, Jeannetay, and Michel—“Note stir la Néphrite ou jade de Sibérie” (_Bul. Soc. Minéralogique de France_, 1881). Meyer: “Die Nephritfrage kein ethnologische Problem,” Berlin, 1882.