An introduction to medical literature, including a system of practical nosology : intended as a guide to students, and an assistant to practitioners / by Thomas Young.

  • Thomas Young
Date:
1813
Catalogue details

Licence: Public Domain Mark

Credit: An introduction to medical literature, including a system of practical nosology : intended as a guide to students, and an assistant to practitioners / by Thomas Young. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

    564/622 (page 534)
    will require us to change the number 1|, for the combinations of this metal, into some whole number yet undetermined : and I have observed that we have reason to infer, from the number 1|, which occurs in the progression of the oxydation of iron, that there is an oxyd of this metal in a lower stage of oxygeniz- ation, yet unknown to us. [In the same manner the existence of a compound, resembling the euchlorine of Davy, was in- ferred by Berzelius before its actual discovery. P. 608.] Rem. 3. In most of my experiments, I have found the pro- gression to consist of even numbers, 2, 4, 6, 8; gold and am- monium exhibit the odd numbers 3, 5, 7, in their stages of oxy- genization; but this irregularity may perhaps depend on tlie existence of some intermediate steps, which are hitherto un- known. Rem. 4. There is a certain proportion between two positive and negative bodies, which affords a combination more intimate- ly united, than any other proportion differing from it on either side. For instance, the oxygen of the oxydiole or protoxyd, oxidule, of mercury is more easily expelled than that of the oxyd; while on the contrary the oxygen of the oxyd of iron is more easily expelled than that of the oxydiole. 2. TJie proportions between two substances, which are found in union with one or more other substances, are governed by the same laws which are observed in their simple binary combinations. For example, the proportion of iron to sulfur in the sulfated oxydiole of iron, or the green sulfate, is precisely the same as in the subsulfuret of iron; and if we compute the proportion of sulfur to metalUc iron in the sulfated oxyd of iron, or the red sulfate, we find that the iron is combined with half as much more sulfur as in the former case; and in the subsulfated oxyd, only J as much. If we recollect, that in the common pyrites the iron is united with twice as much sulfur as in the sulfate of the protoxyd, we shall have for the whole series, first, sulfur 14.687 parts to 100 of iron; next, in magnetical pyrites, and