681 



MERCURY, MEDICAL PROPERTIES OF. 



MERCURY. 



tory diseases. On the salivary glands the effects are most conspicuous ; 

 they become irritated, more sensible, turgid, and pour out abundant 

 saliva, which, on standing, deposits flakes of coagulated albumen. The 

 breath at the same time acquires a peculiar fetor (called mercurial) ; 

 the gums are swollen, with a peculiar line running along the margin, 

 but pale and tender ; the teeth become loose ; and the tongue and 

 lining membrane of the mouth are covered with ulcers. 



The general commotion of the system often proves a powerful agent 

 in the cure of many diseases ; but occasionally it becomes too great, 

 and requires to be moderated. Not only must the exhibition of the 

 mercury be suspended for a time in such cases, but very plethoric 

 persons must be bled, and put on the antiphlogistic plan even before 

 beginning ita use. The warm bath, diluent drinks, and a milk or 

 farinaceous diet, with cool air, are proper means of lessening the 

 violence of its action. Iodine is said to have the power of expediting 

 the removal of the mercury out of the system. 



The effects just mentioned show the necessity of abstaining from 

 its administration when there is a tendency to haemorrhage (especially 

 of the lungs), or a disposition to consumption, or if there exist a 

 scrophulous constitution, or the person be affected with sea scurvy ; 

 also during certain states of the female system, and during pregnancy 

 or suckling. 



When the use of mercury is too long continued, or it is given in too 

 strong doses, ita stimulating action appears to fatigue the system, and 

 to pervert the function of assimilation, both immediately in the blood 

 and also in the different organs and tissues. Hence the individual loses 

 his muscular power, becomes pale, tumid, and puffy, or else greatly 

 emaciated. The brain and spinal chord are irritated ; the limbs 

 exhibit involuntary tremblings, such as are observed in the workers in 

 the mercurial mines, in makers of looking-glasses, and other trades in 

 which mercury is largely used ; and all the tissues acquire a morbid 

 susceptibility. The blood is found to be deteriorated, and to 

 have lost its ordinary consistence, and the person appears to be affected 

 with scurvy or consumption. The inconsiderate use of mercurial pre- 

 parations, especially of corrosive sublimate, often occasions chronic 

 inflammation of the stomach, causing indigestion, and alterations or 

 thickenings of the coats of the stomach. Diseases of the brain not 

 unfrequently result from an improper use of mercury. Lastly, a 

 peculiar affection of the skin often occurs from the abuse of this 

 substance. 



In the treatment of diseases, four distinct effects may be obtained 

 from the employment of mercurial preparations. 1. By some of them 

 the intestinal canal is irritated, and the expulsion of its contents occa- 

 sioned. 2. Others are used to create a general commotion of the system, 

 to rouse the lymphatics, and excite both the secreting and excretory 

 glands. 3. To control or altogether change the action of the capillary 

 vessels, when that is extreme and tending to the effusion of serum, and 

 more especially of coagulable lymph. With this may perhaps be joined 

 the action of the mercury as an alterative. 4. What is regarded as its 

 specific effect in bringing about the cure of some peculiar diseases. 



Calomel, or the protochloride of mercury, is the preparation most 

 employed as a purgative ; it influences the intestinal canal along its 

 whole length, and excites the liver and other glands to secretion. It is 

 of very great utility, not only at the commencement of fevers, but even 

 during their course, either when given alone or in conjunction with 

 some other purgative. It is not admissible if the tongue be very red 

 and sensible, and a similar state of stomach be presumed to exist. In 

 many eruptive fevers, especially scarlet fever, its early and even free 

 employment is productive of the best results. In the yellow and many 

 other fevers of hot climates it is indispensable. In these diseases, mer- 

 cury is introduced into the system by every means ; and whenever the 

 patient is salivated recovery may be expected. In many of the less 

 rapid fevers of Europe the like benefit follows its use. 



During the inflammatory and turgescent stage of hydrocephalus 

 acutiis, or water on the brain, calomel, alone or with digitalis, is 

 frequently efficacious in saving the patient ; at the same time other 

 forms of mercury, especially the liniment, may be used. In the 

 wasting or atrophy of children, the steady daily use of calomel and 

 rhubarb produces the best results, if proper dietetical means be 

 adopted. 



These measures should at no time be resorted to except under the 

 direction of responsible medical attendants. The unnecessary use of 

 mercury, when some other purgative would have answered as well, is 

 much to be reprobated, and not only injures the constitution of 

 children, but, if they are teething at the time, it leads to the early 

 decay of their teeth. (Bell ' On the Teeth.') 



Persons under the influence of mercury, even when a single dose 

 hag been taken an a purgative, are very liable to take cold, especially 

 from wet. This must be carefully guarded against. The bichloride of 

 mercury (or corrosive sublimate) seems not to dispose the system so 

 much to be hurtfully inipn- -r<l by cold, and is therefore well suited 

 <np and navy practice. Besides, if given in sufficiently small doses, 

 it in perhaps the best of all the preparation* to use as an alterative, 

 especially in cases of chronic inflammation or thickening of the tissues, 

 such as the heart. This particular preparation of mercury seems to 

 exert a beneficial effect, in restraining the escape of the albumen of the 

 blood by the kidneys, in the disease called albuminuria, or Bright's 

 disease. It should be given in very minute doses, the j^th of a grain, 



dissolved in distilled water, about half an hour after each meal. If any 

 signs of salivation manifest themselves it should instantly be suspended. 

 Indeed from time to time it should be discontinued, as no system can 

 bear the continuous use of mercury. 



Mercury has a great power of checking the deposition of coagulable 

 lymph, and controlling changes in the organic particles of bodies, both 

 vegetable and animal. One of the most valuable uses of mercury is con- 

 nected with this power of changing the action of the capillaries \\ hen that 

 action is extreme, or when there is a tendency to pour out serum in 

 excess, or effuse coagulable lymph. In some inflammations the action 

 of the vessels is so violent as to pour out their contents, and this leads 

 to obstructions or changes of structure which derange the functions, 

 or even speedily occasion death. Thus, in croup, coagulable lymph is 

 effused in the windpipe, obstructing respiration ; in peritonitis, or inflam- 

 mation of the outer lining of the intestines, lymph is poured out, 

 agglutinating the folds of the intestines ; in iritis the same happens, 

 closing the pupil of the eye and destroying vision. In all these cases, 

 after free venesection, or even without it, calomel given very freely 

 will hinder further effusion, and even cause the absorption of what has 

 already escaped from the vessels, as may often be seen when the iris of 

 the eye is inflamed. 



Many serious chronic diseases are removed by a judicious and perse- 

 vering use of mercury ; but these can neither be enumerated here, nor 

 can even the most general rules be attempted to be laid down. 

 (Holland, ' Medical Notes ; ' ' On Mercurial Medicines ; ' and Teale, ' On 

 Neuralgic Diseases.') 



The specific employment of mercury is still less suitable to be 

 discussed here. It may be remarked, however, that the opinion for 

 the necessity of giving mercury in any quantity is now altogether 

 exploded. 



It is not necessary to dwell on any of the other preparations of 

 mercury, many of which are valuable, either alone or as additions to 

 other substances. Calomel frequently greatly assists in promoting the 

 action of other medicines, particularly diuretic medicaments. How 

 far calomel, either in small frequently repeated doses or in very large 

 ones, was really useful in Asiatic cholera, cannot be ascertained. But 

 where it has been given, and salivation has occurred, or the mercurial 

 fetor of the breath perceived, recovery has almost invariably ensued. 

 The employment of corrosive sublimate in the arts depends in some 

 cases on principles explained above. Thus it checks fermentation, and 

 opposes the formation of new compounds : hence, when applied in 

 solution to timber, it prevents the dry-rot from occurring by solidifying 

 the albumen of the wood. [ANTISEPTICS.] In cases of poisoning by it, 

 the antidotes most proper are those substances which contain albumen, 

 such as white of egg, milk, flour, &c. [ALBUMEN.] (See ' Observations 

 Relative to the Science and Art of Medicine,' by William Wegg, M.D., 

 London, 1851.) 



MERCURY, the planet nearest to the sun. Its orbit being entirely 

 within that of the earth, it never recedes to the point of the heavens 

 opposite to the sun, but is always found within 29' of the sun. Hence 

 it is only visible to the naked eye in the evening, when it is to the east 

 of the sun, and near to its greatest distance (or elongation) from the 

 sun ; so that the sun can descend sufficiently below the horizon to 

 allow the planet to be seen just before its setting : similarly, it is only 

 visible in the morning (before sunrise), when it is near its greatest 

 elongation westward of the sun. The phases of Mercury are not visible 

 without a telescope. The apparent diameter of Mercury varies from 

 5 to 12 seconds ; the real diameter is '398 of that of the earth, or 

 about 3140 miles. Its bulk is to that of the earth as (S3 to 1000; 

 its mass is reckoned at the two-millionth part of that of the sun. It 

 revolves on an axis, the inclination of which to the ecliptic is not 

 determined, in 24 h 5' 28"'3. It has seven times the light and heat of 

 the earth. 



The transits of Mercury, or passages of the planet over the sun's 

 disc, take place when the conjunction (the inferior conjunction, as it is 

 called, Mercury being between the earth and the sun) happens at the 

 time that the planet is near its node. These transits are not so useful 

 in the determination of the sun's parallax or the longitude of the place 

 of observation as those of Venus : we shall therefore refer the account 

 of such transits in general to the latter planet. The following are, 

 according to Delambre, the times of the transits which will yet take 

 place in the present century (civil time at Paris) : 



1861 12 Nov.,7J A.M. 

 1868 5 Nov., 7 A.M. 

 1878 6 May, 7 P.M. 



1881 8Nov.,lA.si. 

 1891 10 May, 3 A.M. 

 1894 10 Nov., GJ P.M. 



EUmentt of the Orltt of Mercury. 



Epoch, 1799, December 31, 12 h mean astronomical time at 

 Seeberg. 



Semiaxis major '3870938, that of the earth being assumed as the 

 unit. 



Excentricity '2041704; its secular increase (or increase in 100 years) 

 0000039. 



Inclination of the orbit to the ecliptic 7 0'5"'9 ; its secular increase 

 18'"4. 



Longitudes from the mean equinox of the epoch : (1.) of the ascend- 



