THE POSE OF THE BODY. 397 



to avoid taking too wide a range of discussion, we shall treat the sub- 

 ject as though the influence of the plane of vision were in all cases 

 uniform, which is not strictly the case; yet, for our present purpose, 

 we may omit the exceptions, and the statements that follow must be 

 accepted as general and as including the proviso, other things being 

 equal. 



Examining then the pose of the head and body in their relations 

 to the position of the visual plane more in detail, it will be found that 

 when the visual plane is quite low not only is there a tendency for the 

 individual to elevate the chin and throw the head back, but the muscles 

 of the whole back, even those of its lower 'part, are put in a state of 

 tension. This tension is so considerable that in a great many in- 

 stances among persons who are not very strong the resulting habitual 

 pains of the muscles engaged are often mistaken and treated for diseases 

 of internal organs or of the spine year after year. 



An element of the facial expression with this direction of the visual 

 plane is the pronounced elevation of the brows upon the forehead 

 and the somewhat drooping appearance of the eyelids (see Fig. 4). 

 There are other facial expressions characteristic of this depressed plane 

 of vision which may be passed over in this connection. 



The attitude and gait of the individual are also generally influenced 

 by the downward direction of the visual plane. In walking the 

 shoulders are thrown back and the chest is thrust forward. The foot, 

 in many cases, swings forward considerably beyond the limit of the 

 completed step, so that it is drawn somewhat backward as it comes to 

 the ground. 



While persons of this class are more liable than others to certain 

 physical complaints and nervous disturbances which can be traced 

 directly to this ocular condition than are those whose eyes are adjusted 

 for a higher plane, they are, on the other hand, compared with this 

 latter class far less subject to certain other forms of diseases and affec- 

 tions. 



A single example will serve to illustrate this proposition. Although 

 the illustration relates to a trouble with the eyes themselves it would be 

 easy to present many examples to illustrate immunity of the same class 

 of persons from a variety of more general affections. 



A few years since a distinguished oculist of one of our southern 

 cities aimounced that trachoma, that form of eye trouble commonly 

 known as granular lids, and which is one of the prolific sources of 

 blindness, is unlcnown among pure negroes. The discussion of this 

 proposition, after occupying the attention of oculists for some time, 

 was at length taken up in a different way by a distinguished colleague 

 in Constantinople. 



This gentleman wrote to oculists in all parts of the world asking 



