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Author : Le Bon Gustave
Title : The Pocket Cephalometer, or Compass of Coordinates, Allowing One to Very Rapidly Obtain the Diverse Diameters, Angles and Profiles of the Head, and To Reproduce in 3-D Any Solid Figure
Year : 1929

Link download : Le_Bon_Gustave_-_The_Pocket_Cephalometer_or_Compass_of_Coordinates.zip

The instruments used up to now in anthropology laboratories to measure the diverse diameters, curves and angles of the head, either upon the living or upon skeletons, are complicated, expensive and by no means portable. What has resulted is that the majority of anthropological measurements have orùy been effectuated upon skeletons, and it is most rare to see a travelling scientist bring back any craniometric measures of races visited by hlm. Taking central Africa as an example, already thoroughly travelled through by many explorers, information on head measurements is wanting in a nearly absolute way. A simple, inexpensive instrument, easy to handle and extremely portable would obviously render important services. The instrument that I have fancied, and which has been manufactured from my designs by a master builder, Monsieur Molteni, entirely realizes the conditions that I have just enumerated. It is extremely portable being that, as will be demonstrated, it can be stored in a carry case possessing ordinary dimensions. Its operation and handling is very easy because orùy a few minutes of use is sufficient in order for one to succeed in supplying himself the desired information. Finally, its priee is not at all high. I have bestowed upon this cephalometer the name compass of coordinates, by reason of the geometrie principles upon which it is founded. One knows that in analytic geometry coordinates are named for the elements which permit for the fixing of the position of a point or a series of points either upon a plane or in space. Given two axes set perpendicular to each other, the horizontal one or axis of the abscissas, the other or axis of ordinales being vertical, the position of various points are determined whenever one knows their distance from these two axes, that is to say, when one knows their abscissas and ordinates. These distances constitute the coordinates of these points. If one can imagine a third axis bisecting the two others, the position of a point in space can be determined if one knows its coordinates, meaning its distances from these three axes. ...