means of a bronze tool used in conjunction with sand and water. He mentions some stone axes found in Bohemia, and in the collection of the Baron de Neuberg, at Prague, which have so little space left between the body of the axe and the central cores, that in his opinion they must have been bored by means of a metal point and not of a hollow cylinder. Mortillet[1] thinks that some of the Swiss axes were bored in a similar manner. The small holes for suspension, drilled through some of the Danish celts, he thinks were drilled with a pointed stone.[2] Not having seen the specimens cited by M. Troyon, I am unable to offer any opinion upon them; but it appears to me very doubtful whether anything in character like a lathe was known at the early period to which the perforated axes belong, for were such an appliance in use we should probably find it extended to the manufacture of pottery in the shape of the potter's wheel, whereas the contemporary pottery is all hand-made. M. Desor,[3] though admitting that a hollow metallic tube would have afforded the best means of drilling these holes, is inclined to refer the axes to a period when the use of metals was unknown. He suggests that thin flakes of flint may have been fastened round a stick and thus used to bore the hole, leaving a solid core in the middle. I do not however think that such a method is practicable. In some of the Swiss[4] specimens in which the boring is incomplete there is a small hole in advance of the larger, so that the section is like that of a trifoliated Gothic arch. In this case the borer would appear to have somewhat resembled a centre-bit or pin-drill. In others[5] the holes are oval, and must have been much modified after they were first bored. The process of boring holes of large diameter in hard rocks such as diorite and basalt by means of tubes was in common use among the Egyptians. These tubes are supposed to have been made of bronze, and corundum to have been employed with them. Professor Flinders Petrie[6] has suggested that they had jewelled edges like the modern diamond crown drill, and that they could penetrate diorite at the rate of one inch in depth for 27 feet of forward motion. I think, however, that this is an over-estimate. Saws of the same kind were also used.
Kirchner,[7] the ingenious but perverse author of "Thor's Donnerkeil," considers that steel boring tools must have been used
