Pharmacologia : being an extended inquiry into the operations of medicinal bodies, upon which are founded the theory and art of prescribing / by J.A. Paris.

Date:: 1843

Credit: Pharmacologia : being an extended inquiry into the operations of medicinal bodies, upon which are founded the theory and art of prescribing / by J.A. Paris. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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$be readily imagined; De Saussure and Bertliier have proved it by their analyses, and Professor Liebig has proposed a theory which will go far to explain the fact. As a general proposi- tion it may be stated that the presence of alkaline bases are essential to the due developement of a plant, and that when roots do not find their more appropriate base in sufficient quantity, they will take up more of another ; but what is more important, the peculiar organic bases are found to vary in an inverse proportion with the fixed or mineral bases; a maximum of the former corresponding with a minimum of the latter, as must necessarily be the case, if they mutually replace one another according to their equivalents; and so also with re- gard to the acids with which they exist, so as to form salts. In all the species of Cinchona, kinic acid is found; but the quantity of Qidna, Cinchonia, and Lime which they contain, is most variable. We also know that different kinds of opium contain meconic acid, in combination with very different quan- tities of narcotina, morphia, codeia, &c., the quantity of one of these alkaloids diminishing on the increase of the others. Thus, the smallest quantity of morphia is accompanied by a maximum of narcotina. Robiquet did not obtain a trace of meconate of lime from .3001bs. of opium, whilst in other kinds the quantity was very considerable, {Ann. de Chim. liii. p. 425,) but in the former case there was not an absence of acid, for the meconic was replaced by the sulphuric acid. If then it be found that an organic may be replaced by an inorganic acid, we must admit the probability of this substitution taking place in a much higher degree in the case of the inorganic bases. If we entirely cut off the supply of inorganic bases, as happens when potatoes are grown in cellars, a true organic alkali, called solanina, of a very poisonous nature, is formed in ' the sprouts which extend towards the light, while not the smallest trace of such a substance can be detected in the roots, lierbs, blossoms, or fruits of potatoes grown in fields. Thus, ^ then, may we easily understand how the soil may influence the I composition and medicinal efficacy of a plant. Rhubarb, as ] grown in England, will differ greatly in its purgative qualities,$