The disagreement in question was between Alfred Lucas and Flinders Petrie about how holes were drilled in hard stones by the ancient Egyptians. An Old Kingdom sarcophagus (ca 2500 BC) was investigated by studying silicone impressions of the holes in the scanning electron microscope and comparing the results with those of holes drilled experimentally by various methods. Sand and crushed quartz were ruled out as possible abrasives; emery, corundum or diamond powders could have been used. The results were not consistent with the use of loose, dry abrusives (except diamond), but were consistent with the use of abrusives in a liquid slurry or bonded to the drilling bit in some way. See also AATA 16-806, 16-1625, 17-680, and 21-921. -- AATA