Waters that do not contain lime are flat and insipid, while a proportion of from 7 to even 20 gr. of carbonate in the gallon is compatible with their being good, wholesome, and pleasant (Parkes); such waters may be rendered sufficiently "soft" by boiling. Hardness dependent upon a soluble bicarbonate of lime is best treated by Clark's process, of adding slaked lime, which precipitates an insoluble carbonate.

Lime sulphate is contained in water from selenitic rocks, and a proportion of from 6 to 21 gr. per gallon must be considered unwholesome; it is liable to irritate the bowels, causing alternately diarrhoea and constipation, as was verified, especially in some prisons and hospitals of Paris, by Parent Duchatelet; such water is not much softened by boiling.

Nitrate of lime is sometimes found in drinking water, being derived probably from organic sources; it is likely to cause diarrhoea.

Water from magnesian limestone, containing magnesia with some carbonate, and 4 to 12 gr. per gallon of sulphate of lime, has been considered specially likely to cause goitre; but professional opinion, though still divided on this question, is now more inclined to the negative view.

Dr. McClelland (in an able report on the medical topography of Bengal) certainly gave remarkable instances from many villages scattered over a large district where the inhabitants, though living close together, were affected with goitre or not, according as to whether they drank or not of certain wells, to which they were restricted according to caste; and he found that the wells used by goitrous persons contained up to 25 per cent. carbonate of lime (Abstract in British and Foreign Review, 1861, i., p. 42; and Watson's "Practice of Physic," vol. i., 3d ed.); the presence of magnesia is not mentioned. Dr. Inglis, in his treatise on the subject, Dr. Coindet, of Geneva, and other authorities, have agreed in blaming lime-waters mainly for the production of goitre, and its greater prevalence along ranges of lime-rock, as in Nottinghamshire, Derbyshire, and in parts of South America, are quoted in favor of the same view. Some connection has been further traced between this cause and cretinism, as well as goitre; and Kolliker and others maintain, not without the support of post-mortem evidence, that by the habitual use of such lime compounds ossification is increased at the base of the skull, so that the cranial foramina become narrowed, and the supply of blood to the brain lessened (British and Foreign Review, January, 18G1, p. 46). On the other hand, Dr. Mitchell has published a careful report upon the "Nithsdale neck," prevalent in that part of the south of Scotland, and has shown that some other element than water must be concerned. It is true that many of the wells used contained from 4 to 14 gr. of carbonate in the gallon (with magnesia), but that limit is compatible with health, and several wells in the same district contained the same quantity, and even to 24 gr., without the production of any goitre (British and Foreign Review, April, 1862).

Synergists

Alkaline and earthy bases have a similar absorbent action to that of the carbonate of lime, and reconstituents generally, such as iron and cod-liver oil, are adjuvants to the lime phosphates; aromatics also are often well combined.

Antagonists And Incompatibles

Mineral acids, laxatives, and irritants either decompose or neutralize the action of lime compounds, with the exception of phosphoric acid, which is sometimes used with the acid phosphate, to render it more soluble.

Saccharated lime is said to be a specially good antidote to carbolic acid, and the following is Ferraud's formula: - R. Sugar 15 parts, water 40 parts; dissolve, and mix thoroughly with quick-lime 5 parts (Lancet, i., 1876).

Hypochlorite of lime is an antidote for sulphuretted hydrogen.

Therapeutical Action (External)