Active Ingredients. - Sarsaparilla contains, besides a varying amount of starch, a volatile oil, and a white crystalline principle, Smila-cine, of which the chemical formula is not yet settled. Smilacine is nearly insoluble in cold water; boiling water dissolves it, and the solution, when shaken, lathers like soap. The reaction is neutral; the taste bitter and acrid.

Physiological Action. - This is in a state of complete uncertainty. I am not aware of any experiments with the volatile oil; and the results of researches upon smilacine are conflicting, but, on the whole, negative. Boecker, whose authority as an experimenter is very high, concludes, from researches which he made with the assistance of Groos, that smilacine is at least entirely devoid both of diuretic and of diaphoretic power, and that it does not cure syphilitic maladies. On the other hand, the experiments of Pallotta seem to show that in some persons at any rate, large doses (7 or 8 grains) of smilacine produce gastric uneasiness, slowing of the pulse, vomiting and perspiration, with faint-ness. There have been no methodical experiments with smilacine upon animals.

Therapeutic Action. - Of the modus operandi of sarsaparilla it must be confessed that nothing is known; even those who are warm-est in its praise will admit this fact. As to the supposed sudorific and diuretic effects, although it seems a comparatively simple point, there are very contradictory opinions, many believing that it is only when large quantities of a warm decoction are taken that any sweating or diuresis is produced, and that these effects are in reality due merely to the warmth of the fluid, and to the quantity of water which accompanies the medicine. I am convinced, however, that diaphoresis is one of the most common and genuine results of sarsaparilla.

Sarsaparilla was introduced into medicine as early as 1560, when it was employed in Venice as a cure for syphilis. It long enjoyed high repute, but gradually became more and more neglected, till at last, Cullen allows only eight lines of description to its history and qualities together, and declares that he cannot give it a place in the Materia Medica, never hav-ing found it useful in any disease! Its restoration to favor, if not to a great place in medicine, we owe to Dr. William Hunter. It must be admitted, however, that even at the present day, there are many who believe Cullen to have been right. Two or three explanations may be given of the disfavor of sarsaparilla: the difficulty of explaining its action, the possibility of removing certain forms of venereal disease with-out resorting either to mercury or to sarsaparilla, and the probability of a spurious article being mingled with or substituted for the genuine one, either by accident or design, before it comes into the hands of the prac-titioner.

The general properties of sarsaparilla are alterative and tonic, and the most common result of its administration is diaphoresis. The continued use of this medicine is often followed by improvement of the appetite and the digestion, and consequent increase of flesh and muscular power. Should there be eruptions, ulcerations, or pains of a rheumatic character in any part of the body, these are often mitigated, and in some cases entirely removed. The best effects are seen in those depraved conditions of the system which are popularly attributed to the presence of some morbid poison, or to a deranged condition of the fluids, whence its fami-liar repute as a "purifier of the blood." It is of special service in second-ary syphilis, either alone or in combination with other remedies, evincing powers of a very serviceable kind when the disease resists the action of mercury, or when it has been aggravated by the use of mercury.

For Simple Debility, and for the cure of intermittents, sarsaparilla is useless, or, at all events, not adapted. It differs in several respects from the bitter vegetable tonics, and possesses very little of the bitter-ness.

In Constitutional Syphilis, after many changes of fortune, sarsa-parilla still holds its ground as a most important remedy, and more especially when employed as an auxiliary to mercury, and in cases which resist the action of that drug, or in which mercury having been freely used, the constitution requires to be rescued from sundry evils which are the result of the mercurial treatment, or of the mercury and the syphilis combined. With respect to this point, it will be interesting to cite first the older British authors, and then to quote at length one of the latest summaries of the action of the drug as given by a highly competent German authority. Sir William Fordyce recommended sarsaparilla more particularly as an auxiliary to mercury, and as well adapted to purify the system after a long course of mercurial treatment. Pearson supports this view, remarking that the contagious matter of syphilis and the mercury together may, in certain habits of body, co-operate to produce a new set of symptoms which, properly speaking, are not venereal. These secondary symptoms (which are sometimes more to be dreaded than the simple and natural effects of the venereal virus) cannot be cured by mercury. Some of the most formidable of them may, however, be removed by the use of sarsaparilla - the virus still holding its ground, though partially giving way - and when by the renewed use of mercury the virus has been completely subdued, sarsaparilla frees the patient from what may be called the sequelae of the mercurial course.

Dr. Good says that he has found sarsaparilla to succeed chiefly in chronic cases, when the constitution has been broken down, and this whether resulting from a long domination of the disease, or from protracted and apparently inefficient mercurial treatment. In connection with a milk diet and country air, Dr. Good continues, sarsaparilla is of essential importance. The majority of medical men coincide with the opinions of Dr. Good and Mr. Pearson. Quite recently, Dr. Clifford Allbutt, of Leeds,1 has given strong testimony to the good effects of sarsaparilla, as observed both by himself and by his colleagues at the Leeds Infirmary, provided that the remedy be administered in large quantities - not less than a pint of the compound decoction in twenty-four hours. He speaks especially of its restorative effects in old and broken-down cases of constitutional syphilis.