In such instances the application of a strong alcoholic resorcin lotion, ten to twenty-five per cent. strength, repeated several times daily till marked irritation and exfoliation occur (a matter usually of one to three days), will sometimes be followed by marked improvement. Acne of the back is treated with the same applications, but usually stronger; in this region applications of Vleminckx's solution and formaldehyde solution, weakened considerably, at first at least, prove of value.

Obstinate and indurated lesions may be incised, the contents pressed out, and the interior touched with carbolic acid by means of a pointed stick. The x-ray has proved a most valuable addition to our resources in the treatment of acne, and is especially serviceable in extensive and obstinate cases. An exposure should be made about twice weekly, at a distance of five to ten inches and for from three to ten minutes, and a tube of medium vacuum used. It must be used with great caution and never beyond the production of the mildest erythema. The hair, eyes, and lips should be protected. The x-ray treatment is best reserved for obstinate cases, and then used mildly, and rather as an adjuvant to the ordinary methods than as the sole measure.

What precaution is to be taken in advising a change from a sulphur to a mercurial preparation or the reverse?

Several days should be allowed to intervene, otherwise a disagreeable, although temporary, staining or darkening of the skin results—from the formation of the black sulphuret of mercury.

Acne Rosacea.

Give a descriptive definition of acne rosacea.

Acne rosacea is a chronic, hyperæmic or inflammatory disease, limited to the face, especially to the nose and cheeks, characterized by redness, dilatation and enlargement of the bloodvessels, more or less acne and hypertrophy.

Describe the symptoms of acne rosacea.

The disease may be slight or well-marked. Redness, capillary dilatation, and acne lesions seated on the nose and cheeks, and sometimes on chin and forehead also, constitute in most cases the entire symptomatology.

A mild variety consists in simple redness or hyperæmia, involving the nose chiefly and often exclusively, and is to be looked upon as a passive congestion; this is not uncommon in young adults and is often associated with an oily seborrhœa of the same parts. In many cases the condition does not progress beyond this stage. In other cases, however, sooner or later the dilated capillaries become permanently enlarged (telangiectasis) and acne lesions are often present— constituting the middle stage or grade of the disease; this is the type most frequently met with. In exceptional instances, still further hypertrophy of the bloodvessels ensues, the glands are enlarged, and a variable degree of connective-tissue new growth is added; this latter is usually slight, but may be excessive, the nose presenting an enlarged and lobulated appearance (rhinophyma).