Dr. Rees has also found the remedy very advantageous in certain cases of chronic rheumatism, connected with deposition of urate of soda in and about the smaller joints, and partaking, as he properly observes, more or less of the gouty character. By the continued employment of the juice in these cases, in combination with small doses of the tincture of chloride of iron, he has succeeded in effecting the absorption of deposits, which had resisted all other plans of treatment. {Lancet, Dec. 1850, p. 651.)

This acid has been supposed to act through the citrate of potassa it contains, and thus really to coincide in effect with the alkaline salts of the vegetable acids, which are thought to render the blood alkaline by the decomposition of their acid ingredient, and the formation of a carbonate of the base. But when the very minute proportion of citrate of potassa which it contains, as determined by Dr. H. Bence Jones, is considered, this explanation of its mode of operation must be admitted to be extremely questionable. I have often administered in rheumatism, every two or three hours, ten times the quantity of citrate of potassa contained in a fluidounce of lemon-juice, without any obvious effects, other than such as usually flow from refrigerant diaphoretics.

Another and much more important application of lemon-juice is to the cure and prevention of scurvy. There is, perhaps, no other single remedy which exercises a more powerful influence over this disease. it should be drank freely in the form of lemonade, and two or three fluid-ounces or more should be given daily. it is of the greatest importance, however, that the juice should be of good quality, and well preserved. it should be made from sound lemons or limes; and, if taken upon long voyages, should be prepared in one of the two following methods. First, lightly boil the juice, then strain, and, after having allowed it to become quite cool, pour it into bottles up to their neck, fill the vacant space above with pure olive oil, cork tightly, and seal thoroughly with sealing-wax. Secondly, add to the juice 10 per cent. of brandy, and bottle it, with the addition of the olive oil, as in the first method. Sir Wm. Burnett has published the strongest testimony in favour, not only of the efficacy of the juice prepared in these methods, but of its permanence without change for years. A comparative trial was made, under his direction, of different antiscorbutics. Pure citric acid was, in many instances, found useful as a remedy in scurvy; but lemon-juice seems to have been more successful than this or any other substance, both as a remedy and preventive. (Lond. Med. Times and Gaz., Dec. 1854, p. 635.) The efficacy of the juice has been ascribed to the potassa contained in it, on the score of the fact, ascertained by Dr. Garrod, that the alkali referred to is deficient in the blood of scorbutic patients. But' against this opinion the same objection may be urged as in the case of acute rheumatism; the extremely minute quantity, namely, in which potassa is found in lemon-juice, an ounce of which, according to Dr. Jones, contains only three-quarters of a grain.

Lemon-juice is an excellent antidote to poisonous doses of the alkalies or their carbonates.

It is much used in preparing the citrates of potassa and ammonia, either in the form of neutral mixture or effervescing draught. These, however, will be treated of with the diaphoretics.

It is sometimes used in conjunction with opium or Peruvian bark, under the impression that it advantageously modifies their effects by the substitution of the citrate of their respective alkaloids, for the native salt.

As a topical remedy, the juice has been used for the suppression of uterine hemorrhage after delivery. For this purpose, it has been recommended to introduce a lemon, previously peeled and cut, into the cavity of the uterus, and then to express the juice. The uterus contracts under the stimulus, and closes the bleeding orifices. it has also been useful in sloughing ulcers, and as an application in pruritus of the genitals.

It has recently come into notice as a very effective application in cases of diphtheric exudation, especially in the fauces. (B. and F. Medico.-chir. Rev., Jan. 1866, p. 231.) Either in the form of lemon-juice, or simply dissolved in water, in the proportion of a drachm to eight fluidounces, citric acid is said to be an excellent application to cancerous sores, relieving the pain, and, though not curing, yet favourably modifying the ulcerative process. This application of the remedy seems to have originated with Dr. Beandini, of Florence, Italy, who, having seen great relief in a case of cancer of the mouth, produced by the juice of a lemon which the patient had requested, made a trial first of the juice, and afterwards of solution of citric acid, as an application to cancerous ulcers generally, with very satisfactory results. (Pharm. Journ. and Trans., Dec. 1865, p. 337.)

Administration

Most that is requisite in relation to the mode of administering lemon-juice, and to its dose, has been already stated. Lemonade may be prepared by putting a lemon of medium size, cut into transverse slices, in a pint of boiling water, adding half an ounce or an ounce of sugar, and allowing the liquid to cool; or half a fluidounce of the juice may be simply mixed with half a pint of water, and sweetened to the taste. it is often advantageously administered iced in fevers. A solution of citric acid may be substituted, when lemon-juice is not to be had. The strength of such a solution, equivalent to lemon-juice, has been already mentioned. in preparing a substitute for lemonade, twenty or thirty grains of the acid may be added to a pint of water, and sweetened with sugar which has been rubbed on fresh lemon-peel, or flavoured with the essence of lemon.