The view obtained both by the speculum and the dilator is rather limited, and usually comprises only the anterior portions of the lower and middle turbinated bones, together with the cartilaginous portion of the septum. In order to get a good view of the lower and middle meatus and of the floor of the nose the patient's head should be inclined forward or backward as occasion requires. The student should, however, not be satisfied by simply inspecting the parts, but should aid the eye by the sense of touch, for pathological changes are of common occurrence, and their nature, whether soft and fleshy or hard and bony, erosions of the mucous membrane, or deep ulcerations, can often only be determined by the aid of the probe. In the same manner can the permeability of the meatuses be determined better than by inspection {37} only. In cases where it becomes necessary to determine whether the anterior portion of the septum is of normal thickness, or whether a projection seen through the speculum is due to localized deflection, an instrument called the septometer is of great assistance (Fig. 14). This instrument is similar to the one used by mechanics to determine the diameter of a piece of wood or iron being turned on the lathe. In using it the long straight shanks are introduced one in each nostril, and, being closed upon the septum, the rounded points are gently moved up and down and backward and forward over the bulging portion of the septum. The motion of the index attached to the curved shanks of the instrument accurately indicates the relative thickness of tissue grasped between the points in the nose. By means of this instrument we can thus ascertain whether we have to deal with a deviation or a localized thickening of the septum; for if it is a deviation the index will move but slightly, while it will travel a considerable distance when the points pass over a thickened portion. [Illustration: FIG. 14. Septometer for Measuring Thickness of Nasal Septum.] Although simple in its details, anterior rhinoscopy is often made difficult or altogether prevented by obstacles which are mostly due to malformation of the parts, such as deviation of the cartilaginous portion of the septum, exostoses from the superior maxillary bones reaching into the nasal cavity, adhesion between the anterior portion of the lower turbinated bone and the septum, nasal polypi, anterior hypertrophies of the mucous membrane, and so forth; or they may be due to faulty instruments, as too much pressure in the spring of the dilator; or, finally, they may be caused by want of care in the handling of the instruments, as when the septum is scratched by the edge of the speculum and hemorrhage ensues.