All examinations with a speculum should be preceded by an enema of warm water to wash away the mucous and retained feces in and about the sphincters. Let the patient lie on either side, turning partially on the chest, with knees drawn up, the one uppermost more firmly flexed on the abdomen, and hips so elevated that the speculum, when introduced points or inclines downward, and admits of strong natural light to fall in parallel rays to its axis. Warm the speculum by _dry heat_ over a single blast kerosene stove, where gas is not convenient. A suitable kerosene stove is an indispensible adjunct to an office for heating instruments, water, etc., causing no smell and leaving no deposit of sut on the bottom of vessels as done by gas or alcohol. Use _white_ vaseline as a lubricant; everything that tends to whiteness helps the sight. The vaseline may be squeezed from a tin-foil tube, and the finger not soiled in preparing the speculum for insertion. [Illustration: FIG. 13.—A suitable Kerosene Stove for office use. It is clean, safe, cheap, portable and has perfect combustion.] To prevent the loose tissue from rolling up and being pushed in with the speculum, the patient may assist by holding the upper buttock away, while the physician introduces the instrument with one hand and retracts the opposite buttock with the other. Introduce slowly, giving time for the muscles to relax, bearing in mind that all movements about the rectum and anus must be extremely easy and gentle. The proximal end of the slot must be carried and kept above the external sphincter during the entire course of the examination. It matters not what kind of a speculum is being used, the value of the instrument will greatly depend upon its power to hold this muscle out of the way. A closed end speculum, with a proportionate slot and smooth corners, can be slowly rotated without any difficulty where the mucous membrane is not very loose and baggy and no prominences in the route. But if a hemorrhoid be in the way it will immediately drop in the slot and further progress is thus impeded. When examining above the internal sphincter, especially posteriorly, where the bottom or floor of the rectum forms a cul-de-sac, direct the patient to strain down a little; this effort will throw the mucous membrane out into the speculum, at the same time spreads out and smooths its surface. In looking through a speculum this cul-de-sac of the rectum sometimes appears as a vacancy behind the internal sphincter, and has been mistaken and treated as an ulcer cavity. It often contains a liberal supply of mucous. FISTULA. Fistula in the recto anal region so far exceeds that in any other locality, that its overwhelming predominence here almost entitles it to the exclusive right of the term; while, to those who have given this part of the physical organism special study, the word itself, calls to mind a local condition of disease that is anything but an easy one to manage.