General therapeutics and materia medica: adapted for a medical textbook (Volume 2).

  • Dunglison, Robley, 1798-1869.
Date:
1853
Catalogue details

Licence: Public Domain Mark

Credit: General therapeutics and materia medica: adapted for a medical textbook (Volume 2). Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

    16/520
    of one or both of the great astringent principles of vegetables. This bitter extractive is not affected by heat; but the aromatic oil is, pro- vided the boiling temperature is maintained for some time. Decoc- tion is, therefore, an improper mode of preparation, where the object is to retain the aromatic property. Infusion is the form most com- monly prescribed ; and hence the pharmacopoeias contain officinal in- fusions of all the principal vegetable tonics. Dr. Thomson asserts, that Dr. Chapman, and, following him, Dr. Paris, attempt to prove, that bitterness is essential to tonics; or, in other words, that it is the tonic principle ; but in this, he does those writers injustice. The latter gentleman affirms, that the tonics, derived from the vegetable kingdom, are generally bitter ;—whilst the former expressly says: Concerning the element, which gives the tonic power, some difference of opinion has been entertained. Cullen supposed it to be the same quality as that of bitterness. But though it holds to a considerable extent, there would seem to be no necessary connexion in all cases. Exceptions at least are not wanting, as we see very strik- ingly in opium and digitalis, which are bitter, though not tonic; and, conversely, in many of the metallic articles, which, though tonic, are not bitter in the slightest degree. Nor do we think Dr. Thomson more accurate in his opinion, that part of all the vegetable tonics are [is] digested in the stomach, and the principle, whatever it is, which produces their tonic influence, is thus separated from the other parts; and consequently it is enabled to act with more energy upon the nerves of the stomach: an explanation that can scarcely apply to infusions of vegetable substances; and still less to the active principles of such substances; nor is it more applicable to them when given in a solid form, as in the state of powder, in which the active principle is, in many cases, combined with little more than lignin or woody fibre. It is but necessary, that the fluids of the stomach, or any fluids, should come in contact with the substance in order to extract its tonic virtue • but nothing like digestion—as applied to the physiological process to which alimentary matters are subjected—is necessary. Bitter extractive, as Dr. Paris has remarked, is a great natural tonic. It appears to pass through the body without suffering any diminution in its quantity, or change in its nature. No cattle will thrive upon grasses, that do not contain a portion of this principle; a fact, which is considered to have been proved by the researches of Mr. Sinclair gar- dener to the Duke of Bedford, who remarks, in his Horlus Of ami- neus Woburnensis that if sheep be fed on yellow turnips, which con- tain little or no bitter principle, they instinctively seek for and greedily devour, any provender, which may contain it, and if' they cannot obtain it they become diseased, and die. We are ourselves conscious, Dr. Paris adds, of the invigorating effects of slight bitters upon our stomach; and their presence in malt liquors not only tends to diminish the noxious effects of such potations bv counteracting the indirect debility, which they are liable to occasion,^ but even to render them, when taken in moderation, promoters of digestion. The custom of infusing bitter herbs in vinous drinks is very ancient and universal • the poculum dbsinthiatum was regarded in remote ages as a wholesome