it never, like opium, causes a total alienation of the mental powers, or induces sleep; but, like opium, it excites the sensibility of the brain, and the repeated excitement occasioned by its intemperate use after a series of years wears out mental vigour and activity.” Weddell and others, from the sleeplessness induced by an infusion of Coca, thought that it might contain Theine, but neither he nor Professor Frémy were able to isolate it, although he held that an active bitter principle, which it had not been possible for them to obtain in crystals, was contained in the leaves. The isolation, since, of Cocaine, an alkaloid possessing such curious properties, and the accounts of the use of Coca just narrated, show that the effects attributed to it are more than imagination and the “force of habit.” Whether it does more than deceive or lull hunger, thirst, and fatigue, and how it acts in these respects, are subjects still to be investigated. The effect which travellers have noticed it has on the respiration at high elevations cannot be imaginary. Under the influence of Coca, it has been said, it appears that a new force gradually introduces itself into our organism, as water into a sponge. Gubler thinks that as with tea, caffeine, and theobromine, Coca brings to the nervous system the strength with which it is charged in the manner of a _fulminate_, with the difference, that it only yields it slowly, not all at once. CHAPTER XII. PHARMACEUTICAL PREPARATIONS. =Elixir Cocæ.=—1 in 6 of Simple Elixir. _Dose._—1 to 4 drachms in water is a palatable preparation. =Extractum Cocæ Liquidum= (_Off._). _Syn._—EXTRACTUM ERYTHROXYLI FLUIDUM, U.S. _Dose._—½ to 2 drachms. Coca leaves are exhausted by percolation with proof spirit, the second part of percolate concentrated and dissolved in the first portion, and the strength adjusted so that 1 ounce=1 of leaves; this preparation contains all the properties of the leaf. If freed from the coca wax it is miscible with water and more palatable, and, so purified, if added to port, sherry, or burgundy, in the proportion of half a teaspoonful to a wineglassful (about an ounce to a bottle), it forms an exhilarating mental stimulant. By distilling off the spirit and concentrating by evaporation, a solid semi-alcoholic preparation is obtained about four times the strength of the above, known as:— =Extractum Cocæ.= _Dose._—2 to 15 grains or more, in pills or pastils. =Infusum Cocæ.=—1 in 50 of boiling water. Taken hot like tea with milk and sugar, or with a slice of lemon, it forms a refreshing beverage. In tonsillitis it may be used warm as a gargle. =Pastillus Cocæ Extracti, Coca Pastils.=—2½ grains of the extract in each. _Dose._—One every two or three hours. Coca pastils are good; cocaine cured case of asthma of 15 years’ standing; recommended for hay fever, spasmodic asthma, and post-nasal catarrh.—M.P.C. ii./85,320.