We give an illustration (Fig. 81) of a trepanned skull found in a cemetery in the Yucay valley. A square piece has been cut out by making four regular incisions. The bone shows traces of an ancient inflammation, and many eminent surgeons, including Nélaton and Broca, have not hesitated to attribute the opening, large as it is (seven by six inches), to a surgical operation. If the incisions are carefully examined it is easy to see that they were made with the help of a pointed instrument, such as a clumsily made drill, for instance. Each incision must have taken a long time to make, and we note with ever increasing astonishment that the ancient Peruvians were not acquainted with the use of iron or steel, and that the hardest metal they employed was bronze. [Illustration: 81.] Trepanned Peruvian skull. A few years ago a sepulchre was opened at Chaclacayo, at the foot of Mount Chosica, not far from Lima. In this tomb lay three mummies, of a man, a woman, and a child. Near them lay a human skull, having about the middle of the forehead an opening, measuring some two and a half by two inches. It is of polygonal form, and eight different incisions can easily be made out, which appear to have been made with some notched stone implement. On raising a strip of skin, still adhering to the skull, there was seen on the front part of the sagittal suture a very small perforation, the result either of a wound or of an operation which bad taken place during life. It has been suggested that the piece of bone taken from the skull had been used to make a lance or arrow-head, which was superstitiously supposed by the owner to ensure his victory. This is, however, a mere suggestion, of which no proof can be given. In other party of America discoveries have been made of trepanned skulls, supposed to date from even more remote times than those we have just been considering. A few years ago Professor Putnam found, in the State of Ohio, some old wells idled with cinders and rubbish of all kinds. From one of them, which was deeper than the others, he took several crania, some of which bore evident traces of trepanation. From a mound near Dallas (Illinois) were taken more than one hundred skeletons, all of adults, placed side by side in a crouching attitude. Every one of them had a round opening on the left temple, and in some of these wounds the flint implement which had produced them was still imbedded. It is very evident that we have here tokens of some funereal rite, the meaning of which is uncertain, though it was evidently practised also in districts very remote from Illinois. To mention yet other examples, the excavation of a tumulus of irregular form near Devil’s River (Michigan) has brought to light five skeletons buried u right, whilst a sixth lay in the centre of the tumulus, which was evidently, if w e may so express it, the place of honor. On each of the six crania a perforation had been made after death.