...... [dram]ss-[dram]j
Cerat. simp., ........................ [dram]iv. M.

The various mercurial ointments, especially one of white precipitate,
five to fifteen per cent. strength, are sometimes beneficial.

A compound lotion, containing mercury, which frequently proves
serviceable, is:--

[Rx] Hydrarg. chlorid. corros., ........... gr. ii-viij
Zinci sulphatis, ..................... gr. x-xx
Tinct. benzoini, ..................... f[dram]ij
Aquae, ............ q.s. ad ........... f[Oz]iv.

In extremely sluggish cases the following, used cautiously, is of
value:--

[Rx] Ichthyol,
Saponis viridis,
Sulphur, praecip.,
Lanolin, ............. [=a][=a] ...... [dram]j.

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, hyperaemic or inflammatory disease, limit