An introduction to medical literature, including a system of practical nosology : intended as a guide to students, and an assistant to practitioners. Together with detached essays, on the study of physic, on classification, on chemical affinities, on animal chemistry, on the blood, on the medical effects of climates, on the circulation, and on palpitation / by Thomas Young.

Date:: 1823

Credit: An introduction to medical literature, including a system of practical nosology : intended as a guide to students, and an assistant to practitioners. Together with detached essays, on the study of physic, on classification, on chemical affinities, on animal chemistry, on the blood, on the medical effects of climates, on the circulation, and on palpitation / by Thomas Young. 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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to be decidedly adverse to it. First, the resemblance of the muriatic acid to many other acids inclines us to think, that it must possess the common principle of acidity. Secondly, the resemblance of the dry muriates to other dry salts is much stronger than their analogy to oxyds. And, thirdly, the submuriates would require to be considered as a peculiar class of bodies, consisting of chlorine, oxygen, and the base : and in this case the quantity of the oxygen would not agree, either with that which the acid is capable of taking up in one of its two higher stages of oxygenization, or with that which is capable of combining with the metal. For ex- ample, in the submuriate of lead, the acid is united w ith a quantity of the oxyd, of which the oxygen is [probably] four times [twice] as much as its own. According to Davy, this salt contains chlorine, oxygen, and lead ; and we shall find on calculation, that the oxygen is only “ £ ” [f] as much, as is necessary for the oxydation of the lead ; and such a combination as this is contrary to all our knowledge of the laws of definite proportions. If again we supposed “ eu- chlorine” to exist in this combination, there would remain only “ | ” [|] of the oxygen necessary for the oxydation of the lead ; nor is it any easier to suppose the hyperoxy- muriatic acid present, leaving only | of the oxygen required for the oxydation. The hypothesis is therefore altogether inconsistent with the present state of our knowledge respect- ing the proportions of chemical combinations. [On repeat- ing these calculations, there does not appear to be quite so great an incongruity in the doctrine of chlorine, as our author has persuaded himself. He informs us (P. 284.) that the submuriate of lead consists of 100 acid and 1640 oxyd, which is equivalent to 104 and 1705.6; and the 104, being con sidered as dry acid, will afford 138 of muriatic acid gas, supposed by Sir II. Davy to contain 134 of chlorine, or 2 portions; but the oxyd is denoted by 398 + 30=428, and 4 portions make 1712, exceeding the former number only by Thl

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