In Dyspnæa, attended with a spasmodic condition of the pulmonary organs, vapours impregnated with sulphuric æther have been recommended for inhalation. Dr. Pearson also states that the efficacy of such an application is materially enhanced by dissolving in it a portion of the extract of Conium. Dr. Bôotcher of Copenhagen, has lately announced the utility of vapours of camphor, in complaints affecting the cavities of the nose, throat, and chest. He states that in the worst case of stoppage of the nose from catarrh, a piece of camphor need only be kept for a few minutes before it, to obtain great relief; the same application has been known to produce good in Cynanche Tonsillaris. In order to apply such inhalations we may employ the inhaler invented by Dr. Mudge, or if that instrument be not at hand, the spout of a tea pot, or a common basin with an inverted funnel, will be found very convenient substitutes. REMEDIES OF EXTERNAL APPLICATION. This class of medicinal agents formerly comprised a much wider range of forms than it at present contains; such as numerous _Epithems_; _Vapours_; _Aromatic Bags_; _Medicated Quilts_, _&c._ The external remedies of the present day may be divided into two orders, viz. 1. Those whose effects are entirely _local_, as exemplified in the application of certain _refrigerating_ embrocations, _stimulating_ cataplasms, and _astringent_ unguents. 2. Those which excite general effects, or produce an influence upon parts remote from those to which the remedy is more immediately addressed, as illustrated by the operation of mercurial liniments and unguents, or by the general tonic effects of adhesive plaisters. With respect to the former of these divisions it is unnecessary to multiply our remarks; the objects which they embrace belong more particularly to the department of surgery, and from the investigation of the different modes and forms of external application we shall hereafter derive very ample and instructive illustrations. In considering the objects of the latter division, a very interesting and important question immediately suggests itself for our consideration—How far a medicinal substance, when locally applied to the surface of the body, may be capable of affecting the general system, or some of its more remote parts?—the experienced practitioner will feel no hesitation in admitting numerous proofs of the existence of such agency; and it would seem probable that topical applications may produce general effects by several distinct modes of operation, viz. 1. _By exciting an impression on the nervous system._ 2. _By modifying the cuticular discharge._ 3. _By being absorbed into the circulation._