Mercury or Quicksilver. A metal which, in its pure (liquid) state, is apparently inert, as large quantities of it have been taken without producing any of its physiological effects; but occasionally, when subjected to the action of the secretions of the stomach and intestines, it oxidizes and acquires powerful medicinal properties. Workmen and others much exposed to the vapour of Mercury are subject to tremors, stammering, and other nervous affections, which not unfrequently prove fatal. When rubbed into the skin or administered internally, in a state of minute subdivision, it acts energetically on the system. It is of great importance in medicine, as the base of several valuable preparations and salts.

* Mat. Med., vol. ii. pt. ii. p. 376. Therapeutics, vol. i. p. 285. Obs. on Humulus Lupulus, by A. Freake.

§ Op. cit, p. 13. II Dispensatory, p. 4S4. ¶ Ed. Med. and burg. Journal, No. xlv. p. 244.

Offlc. Prep. 1. Hydrargyrum cum Creta (See art. Hydrargyrum cum Creta.)

2. Pilula Hydrargyri

(See art. Pilula Hydrargyri.)

3. Emplastrum Hydrargyri (Mercury Oz

iij.; Olive Oil fl. oz. j.; Resin oz.j.; Litharge Plaster oz. vj. Melt together the Oil and Resiu; add the Mercury and triturate till its globules disappear; then add the Litharge Plaster previously liquefied). A stimulant and discutient plaster in glandular enlargements and swellings. Sometimes applied over the region of the liver in hepatic enlargements.

4. Emplastrum Ammoniaci Cum Hydrargyro (Ammoniac Oz

xij.; Mercury oz. iij.; Olive Oil fl. drm. j.: Sulphur grs. viij.). A stimulant and discutient plaster used to disperse glandular swellings, especially venereal buboes.

5. Unguentum Hydrargyri

(See art. Unguentum Hydrargyri.)

6. Linimentum Hydrargyri (Ointment Of Mercury Oz J

; Solution of Ammonia fl. oz. j.; Liniment of Camphor fl. oz. j.). Used to excite absorption in chronic tumours and affections of the joints. It is said to produce salivation more readily than the Ung. Hydrargyri, owing to the Camphor and Ammonia it contains.*

1362. Physical Effects Of The Preparations Of Mercury On The System

When taken in moderate doses, they increase the action of the various secreting glands and organs; stimulating some, the salivary glands and liver, for example, in an especial manner. From its power of augmenting the secretions, Mercury is spoken of as a sialagogue, cholagogtie, purgative, diuretic, sudorific, emmenagogue, &c Some of the latter effects are probably rather due to its general action on the system, removing morbid states which interfered with the due performance of the secreting functions of the organs, than to a direct effect on them. Mercury causes in the constitution, in some more than others, a great amount of irritability, making it more susceptible of all impressions. It quickens the pulse, increases its hardness, and occasions a kind of temporary fever, which, however, commonly diminishes when the patient has become habituated to the medicine. This irritation is chiefly observable when it is administered in small doses; in large ones it has been found to calm the system and to act apparently as a direct sedative. If long continued, it produces a specific action on the salivary glands, commonly called Salivation or Ptyalism, which may always be taken as a criterion that the system has become affected. The biliary secretion is also greatly increased, as is evidenced by the copious bilious stools; the blood is impoverished; the patients become thin and pale; and Dr. Farre considers that it destroys the red blood-globules (Globulin and Htematin) as effectually as they may be destroyed by venaeseetion. Mr. H. Smith found, that blood drawn from a person under the influence of Mercury is generally cupped and buffed; that the clot is less solid, and easily broken down, and that there is less cohesion of the principles which form the vital part of the blood. In some cases it will not show any tendency to coagulate; in others it is thick and tarry. Sir B. Brodie observes, that in many instances a course of Mercury renders the urine alkaline; in some individuals, a single dose of Calomel will produce the same effect. In numerous analyses of the urine of patients under the influence of Mercury, Dr. Owen Rees§; failed to detect a trace of albumen. The urine is generally increased in quantity. In the saliva of persons under the same circumstances, Simon || found an increase of solid constituents; and according to Dr. Bostock¶ it is less viscid than in a healthy state, and contains a substance analogous to coagulated albumen. Mercurials produce the absorption of morbid fluids and materials of low organization, e.g. the albuminous matters which are deposited in the tissues in syphilis. It is uncertain whether they produce this effect by directly stimulating the absorbents or by preventing fresh deposition. In large doses, some of the salts of Mercury, particularly the Bichloride, act as irritant poisons.

* Pereira, vol. i. p. 908.

On the Action of Mercury in Inflammation, Med. Times, vol. xvi. 1847.

On Diseases of the Urinary Organs, p. 210.

§ Med. Gaz., July 1851. || Animal Chemistry. ¶ Med. Chir. Trans., vol. xiii.