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CRANIOMETRY
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CRANIOMETRY . The application of precise methods of measurement marks a definite phase in the development of most branches of See also:modern See also:science, and thus craniometry, a comprehensive expression for all methods of measuring the See also:skull (cranium), provides a striking landmark in the progress of anthropological studies. The origin of craniometry appears to be twofold. Certain artists made measurements of heads and skulls with a view to attaining greater accuracy in their See also:representation of those parts of the human See also:frame. See also:Bernard de See also:Palissy and A. See also:Durer may be mentioned as pioneers in such researches. Again, it is clearly shown in the literature of this subject, that anatomists were led to employ methods of measurement in their study of the human skull. The determining cause of this improvement in method is curious, for it appeared at the end of a famous anatomical controversy of the later See also:middle ages, namely the dispute as to whether the Galenic See also:anatomy was based on the study of the human See also:body or upon those of apes. In the description of the See also:dissection of a See also:chimpanzee (in 168o) Tyson explains that the measurements he made of the skull of that See also:animal were devised with a view to exhibiting the difference between this and the human skull. The artists did not carry their researches very far. The anatomists on the contrary continued to make measurements, and in 1764 See also:Daubenton published a noteworthy contribution to craniometry. Six years later, Pieter See also:Camper, distinguished both as an artist and as an anatomist, published some lectures containing an See also:account of his craniometrical methods, and these may be fairly claimed as having laid the See also:foundation of all subsequent See also:work. That work has been described above as anthropological, but as the studies thus defined are very varied in extent, it is necessary to consider the subdivisions into which they naturally fall. In the first See also:place (and omitting further reference to the contributions of artists), it has been explained that the measurements were first made with a view to elucidating the comparison of the skulls of men with those of other animals. This wide comparison constitutes the first subdivision of craniometric studies. And craniometric methods have rendered the results of comparisonmuch more clear and comprehensible than was formerly the See also:case. It is further remarkable that among the first measurements employed angular determinations occur, and indeed the name of Camper is chiefly perpetuated in anthropological literature by the " facial See also:angle " invented by that artist-anatomist (fig. I). It appears impossible to improve on the See also:simple terms in which Camper describes the See also:general results of the employment of this angle for See also:comparative purposes, as will appear from the following brief See also:extract from the See also:translation of the See also:original work: " The two extremities of the facial See also:line are from 70 to 8o degrees from the See also:negro to the Grecian See also:antique: make it under 70, and you describe an ourang or an See also:ape: lessen it still more, and you have the See also:head of a See also:dog. Increase the minimum, and you See also:form a See also:fowl, a See also:snipe for example, the facial line of which is nearly parallel with the See also:horizon." (Camper's See also:Works, p. 42, translated by Cogan, 1821.) In the 9th See also:century the names of notable contributors to the literature of craniometry quickly increase in number; while it is impossible to analyse each contribution, or even See also:record a See also:complete See also:list of the names of the authors, it must be added that for the purposes of far-reaching comparisons of the See also:lower animals with mankind, craniometric methods were used by P. P. See also:Broca in See also:France and by T. H. See also:Huxley (See also:figs. 2 and 3) in See also:England, with such See also:genius and success as have not yet been surpassed.
The second See also:division of craniometric studies includes those in which the skulls of the higher and lower races of mankind are compared. And in this domain, the See also:advent of accurate numerical methods of recording observations brought about See also:great advances. In describing the facial angle, it will be seen that the modern See also:European, the See also:Greek of classical antiquity and the Negro are compared. Thus it is that Camper's name appears as that of a See also:pioneer in this second See also:main division of the subject. Broca and Huxley cultivated similar comparative racial See also:fields of See also:research, but to these names that of Anders Retzius of See also:Stockholm must be added here. The See also:chief claim of Retzius to distinction rests on the merits of his See also:system of comparing various dimensions of the skull, and of a See also:classification based on such comparisons. These indices will be further defined below. It is convenient to mention here that the first aim of all these investigators was to obtain from the skull reliable data having reference to the conformation or See also:size of the See also:brain once contained within it. Only in later days did the tendency to overlook this, the fundamental aim and end
of craniometry, make its See also:appearance; such nevertheless was the case, much to the detriment of craniometric science, which for a See also:time seems to have become purely empirical.
The third subdivision of craniometric researches is one in which the See also: For herein the various sub-racial types such as the dark and See also:fair Europeans are brought together for the purposes of comparison or contrast. But although the range of research is thus narrowed and restricted, the guiding principles and the methods remain unchanged. In this See also:department of craniometry, Anders Retzius has gained the foremost place among the pioneers of research. Retzius's name is, as already mentioned, associated not with any particular angle or angular measurement, but rather with a method of expressing as a See also:formula two See also:cranial dimensions which have been measured and which are to be compared. Thus for instance one skull may be so proportioned that its greatest width See also:measures 75% of its greatest length (i.e. its width is to its length as three to four). This ratio (of 75%) is termed the cephalic or breadth-See also:index, which in such an instance would be described as equal to 75. A B C From See also:Tylor's See also:Anthropology, by permission of See also:Macmillan & Co., Ltd. A skull providing a breadth-index of 75 will naturally possess very different proportions from another which provides a corresponding index equal to 85. And in fact this particular index in human skulls varies from about 58 to go in undistorted examples (fig. 4). Such is the general See also:scheme of Retzius's system of classification of skulls by means of indices, and one of his earliest applications of the method was to the inhabitants of See also:Sweden. 373 One striking result was to exhibit a most marked contrast in respect of the breadth-index of the skull, between the Lapps and their Scandinavian neighbours, and thus a craniometric difference was added to the list of characters (such as stature, See also:hair-See also:colour and complexion) whereby these two types were already dis- tinguished. Since the publication
of Retzius's studies, the cephalic or
breadth-index of the skull has
retained a premier position among
its almost innumerable successors,
though it is of See also:historical See also:interest to
See also:note that, while Retzius had un-
doubtedly devised the method of
comparing " breadth-indices," he
e
C. always qualified the results of its use by reference to other data. These qualifications were over-looked by the immediate successors of Retzius, much to the disadvantage of craniometry. In addition to the researches on the skull
forms of Lapps and Swedes, others dealing with the comparison of Finns and Swedes (by Retzius) as well as the investigation of the form of skull in See also:Basques and See also:Guanches (by Broca) possess historic interest.
Thus far little or nothing has been said with regard to See also:instruments. Camper devised a four-sided open frame with See also:cross-wires, through which skulls were viewed and by means of which accurate drawings could be projected on to See also:paper. The methods of Retzius as here described require the aid of callipers of various sorts, and such instruments were quickly devised and applied to the See also:special needs of the case. Such instruments are still in use, and two forms of simple craniometer are shown in the accompanying illustrations (figs. 5 and 6). For the more accurate comparison required in the study of various European types, delicate instruments for measuring angles were invented by Anthelme in See also:Paris (1836) and See also: H. See also:Flower and Sir W. See also:Turner in England, J. L. A. de Quatrefages in France, J. C. G. Lucae and H.See also:Welcker in See also:Germany. Moreover, the methods have also been multi-plied, so that in addition to angular and linear measurements, those of the capacity or cubical contents of the cranium and those of the curva- FIG. 6.—Flower's Craniometer as moditure of its surface demand fled by Dr W. L. H. See also:Duckworth. reference. The masterly work of See also:Cleland claims special mention in this connexion. And finally while two dimensions are combined in the cephalic index of Retzius, the See also:combination of three dimensions (in a formula called a modulus) distinguishes some See also:recent work, although the employment of the modulus is B 1'homme et dans See also:les animaux," Comptes rendus de l'academie See also:des sciences (Paris, 1764); Camper, Works (1770, translated by Cogan, 1821); Broca, Memoires (1862 and following years); Huxley, See also:Journal of Anatomy and See also:Physiology, vol. 1 (1867); Retzius, Uber See also:die Schadelformen der Nordbewohner (Stockholm, 1842) ; Anthelme, Physiologie de la pensee (Paris, 1836) ; Grattan, See also:Ulster Journal of See also:Archaeology, vol. I (1853) ; Busk, " A System of Craniometry, Transactions of the Ethnological Society (1861); Flower, See also:Catalogue of the Hunterian Museum, See also:Osteology, See also:part 1(See also:London, 1879) ; Turner, ' Challenger ' Reports," See also:Zoology, vol. x. pt. 29, " Human Crania " (1884) ; de Quatrefages, Crania ethnica (Paris, 1873) ; Lucae, Architectur des menschlichen Schddels (See also:Frankfort, 1855) ; Welcker, Bau and Wachsthum des menschlichen Scheidels (1862); Cleland, " An Inquiry into the See also:Variations of the Human Skull," Phil. Trans. See also:Roy. Society (187o), vol. 16o, pp. 117 et seq.; von See also:Baer, " Crania selecta," Academie imperiale des sciences de S. Petersbourg (1859); His and Rutimeyer, Crania Helvetica (See also:Basel, 1866) ; Ecker, Crania Ger- manise meridionalis (1865) ; Thurnam and See also:Davis, Crania Britannica; von Torok, Craniometrie (See also:Stuttgart, 1890) ; Benedikt, See also:Manuel technique et pra- tique d'anthropometrie cranio-cepha- lique (Paris, 1889) ; See also:Pearson, Biome- trika, from vol. 1 (in 1902) onwards;
Sergi, " The Varieties of the Human
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