The Jaw Displaced

On the basis of our preliminary arguments and our anatomical re-examination of the fragments, Mr. W. N. Edwards, the Keeper of Geology of the Natural History Museum, felt justified in allowing the specimens of mandible, cranium, and teeth to be drilled for much larger samples than could ever have been sanctioned hitherto. These larger samples and the use of improved chemical methods guaranteed a high degree of analytical reliability. The drilling itself gave us an encouraging start. As the drilling proceeded, Dr. Oakley and his assistant perceived a distinct smell of ‘burning horn’ when the jaw was sampled, but they noticed nothing of the sort with any of the cranial borings. This subjective indication of some distinct difference between the constitution of jaw and cranium soon gained objective confirmation. The drilled sample from the jaw proved to be utterly unlike those from the cranium. In keeping with the belief in its fossil or semi-fossilized character, the latter produced a fine particulate granular powder, whereas the jaw yielded little shavings of bone, just as did a fresh bone sampled as a control. Here was the beginning of the series of findings which progressively widened the gulf between jaw and cranium. Very soon Dr. Oakley obtained clear chemical evidence to justify fully the strong suspicion of the modernity of the jaw and of the totally distinct origin of the cranium. An improved technique for estimating small quantities of fluorine produced this decisive result. The cranial fragments of site I were found to contain fluorine in a concentration of 0.1 per cent., a value somewhat similar to that of specimens of known Late Ice Age. The jaw and the three teeth on the contrary gave much lower figures, at levels below 0.03 per cent., values well within the range of known modern and fresh specimens. Indeed, these values are on the borderline of the sensitivity of the method. The fluorine test gave its verdict twice over. For the two cranial fragments from the second Piltdown site contained a fluorine concentration of 0.1 per cent, and the isolated molar which went with these fragments contained less than 0.01 per cent.