other minute particles of dust, while in the case of the tall headed boy (Fig. 16) who has, by actual measurement, the visual plane adjusted more than twenty degrees above the horizon, the larynx forms a hinge-like valve and in the quiet eddies of a lung under these circumstances the tubercle bacilli can easily hold high carnival. If the direction of the large branches of the air tubes is considered it is evident that the circulation of the air in the very upper portions of the lungs of one with such a habitual pose would naturally be even less active than in the lower parts, and it is interesting to remember that it is in the upper lobes that the bacilli usually commence their inroads. The modern treatment of consumption is fresh air. It is evident that the amount of air admitted to the lungs of a person with the habitual attitude of this boy must be very materially modified by this position of the head; and could the normal pose be improved he would by that means be subjected to the fresh-air treatment. It will be seen that this is entirely practicable.
The comparative immunity of the negro race from consumption has already been referred to, and it is a fact of much practical interest that among the people of Iceland, people with the extreme broad head and with the characteristic pose, the head thrown back, the chin elevated, consumption is unknown. Yet these people habitually inhale the most vitiated atmosphere, an atmosphere which, habitually inhaled by the people of this country, would induce an epidemic of consumption which would be of the most devastating character.
As the general pose of the head and the attitude of the body differ in the class with high heads from those of the other classes, so the gait and carriage of these people differ widely from those of the others. If the cake walk is an extravagant exaggeration of the walk of the classes with the low visual plane, the stoop of Shylock as it is represented on the stage is the exaggeration of the carriage of the other class.
This is but a most cursory glance at a most important subject; and the affections and characteristics mentioned are but a group of those whose name is legion and which have for their cause one or other of these visual conditions.
Several years ago attention was called by the writer of this article to the one-sided carriage of the head of those who have the visual line of one eye higher than that of the other. I will only refer to it here as one of the elements in this interesting subject.
The practical question which arises from the presentation of this subject is: Can the direction of the visual axes be so modified in the individual case as to change the pose of the head and body so as to relieve the person from the results of his physical peculiarity? To this an emphatic affirmative answer can be given. The eyes can be adjusted for any desired plane by a safe and speedy procedure. It may be said
