That we spoke at all might rightly be called a work of nature, opera naturale, as Dante said long ago; but that we spoke thus or thus, cosi o cosi, that, as the same Dante said, depended on our pleasure—that was our work. To imagine, therefore, that as a matter of necessity, or as a matter of fact, dolichocephalic skulls had anything to do with Aryan, mesophalic with Semitic, or brachycephalic with Turanian speech, was nothing but the wildest random thought. It could convey no rational meaning whatever; we might as well say that all painters were dolichocephalic, and all musicians brachycephalic, or that all lophocomic tribes worked in gold, and all lisocomic tribes in silver. If anything must be ascribed to prehistoric times, surely the differentiation of the human skull, the human hair and the human skin would have to be ascribed to that distant period. No one, he believed, had ever maintained that a mesocephalic skull was split or differentiated into a dolichocephalic and a brachycephalic variety in the bright sunshine of history. Nevertheless, he had felt for years that knowledge of languages must be considered in future as a sine qua non for every anthropologist. How few of the books in which we trusted with regard to the characteristic peculiarities of savage races had been written by men who had lived among them for ten or twenty years, and who had learned their languages till they could speak them as well as the natives themselves. It was no excuse to say that any traveler who had eyes to see and ears to hear could form a correct estimate of the doings and sayings of savage tribes.