_Each Catalytic tends of itself to work out a peculiar operation in the blood._
This peculiar process, established by their presence in the blood, forms part of the known history of each Catalytic medicine. It will suffice to demonstrate this if I condense into as few words as possible the facts that are known on this subject, with respect to each of the orders of this division of remedies.
Of _Antiphlogistic_ medicines, some possess a power which stamps them at once as likely to be useful in the treatment of inflammatory disorders.
Alkalies are known to have the chemical property of holding Fibrine in solution. By exerting this power in the blood, it seems that they may prevent its abnormal deposition or coagulation in inflammatory cases, and at length diminish it in quantity. On this principle they were proposed and used successfully by Mascagni in acute inflammations. Their efficacy in retarding the formation of crude deposits in scrofulous and tubercular diseases may possibly be assigned to the same operation. Potash has been extolled by Dr. Theophilus Thompson as a powerful preservative for those who are predisposed to phthisical disease. Alkalies in small doses, and in cases requiring them, may be Restoratives.
Salines have been shown by Mr. Gulliver to have the effect of keeping the blood-corpuscles apart from one another. This may partly explain their action; for in inflammatory blood the corpuscles display a peculiar and abnormal tendency to aggregate together in rows. Salines also are solvents of Fibrine.
The immediate action of Mercury in checking inflammation is often very apparent in the case of Iritis. This medicine in some way diminishes the plasticity of the Fibrine of the blood; and probably promotes absorption by preventing in this way a further deposit of lymph. If the blood be analyzed after the continued use of Mercury, it is found to contain less Fibrine than in health. It has also a peculiar action of its own in the blood, for it sometimes produces various eruptions, particularly Eczema, as well as a state called Mercurial fever.
Antimony has various and marked medicinal properties: in large doses Neurotic; in all cases Eliminative. But we are now concerned merely with an agency in the blood. It has certainly some action of this kind. When rubbed on the skin it produces a pustular eruption; and M. Lepelletier gives a case in which it did this when administered only internally. Magendie found that when given to dogs it produced engorgement, and often inflammation of the lungs. Antimony seems to exert a blood-influence over inflammation somewhat similar to that of Mercury; but it further adds to this a powerful sedative effect. Antimony generally arrests inflammation by reducing the pulse; but Mercury reduces the pulse by arresting inflammation.