On the physiological and medicinal properties of bromine and its compounds; also on the analogies between the physiological and medicinal properties of these bodies, and those of chlorine and iodine, with their correspondent compounds / [Robert Mortimer Glover].

  • Glover, Robert Mortimer, 1816-1859
Date:
[1842]
Catalogue details

Licence: Public Domain Mark

Credit: On the physiological and medicinal properties of bromine and its compounds; also on the analogies between the physiological and medicinal properties of these bodies, and those of chlorine and iodine, with their correspondent compounds / [Robert Mortimer Glover]. Source: Wellcome Collection.

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    searches of Mr Blake fall short of what this great question re¬ quires, since their author confines the chemical part of the ques¬ tion on the one hand, and that which relates to physiology on the other. He takes into account almost exclusively the effects of substances introduced directly into the circulation ; and many salts which are very different in general physiological properties, thus introduced, appear to produce very similar effects. Thus he has been led to connect potassa and its salts physiologically with am¬ monia and its compounds, rather than with the series of soda salts, which last named group he places beside the salts of silver, follow¬ ing in this respect the isomorphous relations as guides. Now, in general chemical properties, potassa, and soda, with their respec¬ tive salts, are more allied than are the compounds of sodium and silver, and I venture to assert, that this also holds good physiolo¬ gically. In this inquiry I am most fortunately situated, for, not only are there beautiful chemical analogies to be traced through¬ out the group of halogenous elements and their compounds, but in general the chloride, bromide, and iodide of a base are isomor¬ phous. Although desirous to avoid all chemical details, which are fo¬ reign to the subject, I proceed to indicate some of the leading che¬ mical and physical analogies of this interesting group, for they have a distinct bearing on the inquiry. In the first place, we are struck by the remarkable analogies of physical character in the elementary bodies, which may in general be traced in a modified form throughout the long series of com¬ pounds. Thus, at ordinary temperatures, chlorine is a light-green coloured gas ; bromine a liquid of a splendid red colour ; iodine a solid with an intense shade of violet. And the volatility of their respective compounds in general follows in each case the rule of the element. Hydrochloric acid is the most volatile of the three hydracids, and hydriodic acid the most fixed. The chloride of potassium is volatile at a brown red heat, while the iodide re¬ quires a much more elevated temperament.* Chloride of cyano¬ gen is gaseous at ordinary temperatures when the bromide and iodide of the same substance are solid. The chlorides and bro¬ mides of olefiant gas and formyl are liquid, but the correspond¬ ing iodides are solid. The compounds of bromine are frequently of a deeper hue than those of chlorine, but the compounds of io¬ dine are generally of the deepest shade of all. Nay, the respec¬ tive specific heats of these bodies preserve a relation. It will be observed, in the tables given in the recent researches of M. Reg- nault on the specific heats of compound bodies, that the specific heats of bromides are less than those of chlorides, and greater than «» * Berzelius, Traite de Cliimie, T. iii. p. 374.