The U. S. officinal solution is made by dissolving six drachms of iodine and a troyounce and a half of iodide of potassium in a pint of distilled water. it will be perceived that it differs from the preceding only in its strength, which exceeds that of the compound tincture by one-third, and in having water instead of alcohol as the solvent. The iodine is dissolved in the water through the agency of the iodide. The preparation is the stronger solution used by Lugol, and hence is frequently called Lugol's solution.

This is a very convenient form for the exhibition of iodine, whenever the object is to give it in a free state, and may be used for all the purposes aimed at through the absorption of the medicine. its disadvantage is that, from the presence of the free iodine, it cannot be increased to the extent which may sometimes be deemed desirable, for fear of producing gastric irritation; and, even in moderate doses, it is more liable to irritate the stomach than if it were a solution of iodide of potassium alone. if the remarks made in a preceding page, in reference to the changes which iodine must undergo previously to absorption, are correct, there can be no occasion for the use of free iodine, when the object is to affect the constitution; and the use of this preparation might be limited to cases, in which it is desired to produce a direct excitant or alterative impression on the alimentary mucous membrane.

The dose is from six to twelve drops, to be gradually increased if necessary, given in a wineglassful of sweetened water, and repeated two or three times a day. in the use of this, as of all the other preparations containing free iodine, should irritation be produced when they are given on an empty stomach, this may subsequently be avoided, in most instances, by administering the dose after a meal.

This preparation may be used for inhalation, embrocation, injection, bathing, etc.

For inhalation a little of it may be put into an inhaler with warm water, and the vapours inhaled daily, twice a day, or oftener, according to the effects. One or two fluidrachms may be mixed with half a pint of water, and the proportion increased or diminished according to the effect. Should an irritant impression be produced in the air-passages, the quantity should be lessened so as simply to keep within that point; should no sensible impression result, the proportion may be increased until a slight irritation is caused; and then maintained or diminished.*

* Chloroformic Solution of iodine A solution of iodine in chloroform lias been proposed, both for inhalation, and local application, in the form of vapour. it may be made by dissolving one part of iodine in five of chloroform. in consequence of its insolubility and high specific gravity, it may be preserved under water. it has

For embrocation, it may be used diluted with six, eight, or twelve times its bulk of water.

To produce a strong impression upon limited extents of surface, with the cuticle sound, or for careful application to indolent or fungous ulcers, the solution may be used of its full strength, and should be applied by means of a camel's-hair pencil; but the simple tincture, or a still stronger preparation, is usually employed for these purposes.

For local application to delicate surfaces, as, for example, to the eye in scrofulous ophthalmia, to the nostrils in ozaena, or to the external meatus in chronic otirrhoea, from three to twelve minims may be added to a fluidounce of distilled water; and the proportion increased as circumstances may require. The same course may be pursued in fistulous ulcers, which, however, will often demand a much greater strength for the required impression.

For pediluvium, two fluidrachms of it may be added to a gallon of warm water, and the proportion increased if no irritation result.

For general bathing, a fluidrachm containing about three grains of iodine may be added to each gallon of water, in a wooden bathing tub* been proved that its vapour contains iodine, which may, therefore, be introduced into the system through the lungs. in fifteen minutes after its inhalation, iodine has been detected in the urine. it may be used by simply holding a bottle containing it to the nostrils, and occasionally shaking it so as to favour volatilization. A pungent sensation is first felt in the nostrils and throat, which soon ceases. Of course great care must be taken not to bring the system too strongly under the influence of the chloroform. it may be used for the local effects of iodine on the bronchial tubes, or its general effects on the system. it was introduced to notice by M. Teton, of France. (Stethoscope, v. 366,.from Bullet, de Thérap ) Dr. Calvin G. Page has used this solution with advantage in obstinate granular and scrofulous ophthalmia, applying the vapour over the closed eyelids. it has been proposed to use it also in scrofulous glands, swollen joints, etc., by a similar mode of application. it has the asserted advantage of not discolouring the skin, as when iodine is applied in the liquid form; while it is supposed that, the iodine is probably even more readily absorbed in the state of vapour. (Bost. Med. and Surg. Journ., liii. 284 ) - Note to the second edition.

* Solution in Glycerin. Since the publication of the first edition of this work, a solution of iodine in glycerin has been introduced into use, for local application. in its preparation, as in that of the compound solution, the instrumentality of iodide of potassium is resorted to. One part of this salt is dissolved in two parts of glycerin, and one of iodine is then added, which is completely dissolved. The solution should be spread on the part affected, and then covered with an impermeable tissue to prevent evaporation. it occasions pain, more or less severe, for a time. When it is applied to an ulcerated surface, the iodine wholly disappears in a few hours in consequence of absorption. it has proved extremely useful in lupus; but, either in its concentrated state, or more or less diluted, it may be used in goitre and scrofulous tumours and ulcers, and indeed for all the purposes for which the solutions of iodine are applied to the surface. The concentrated solution acts as a caustic. (Am. Journ. of Pharm., xxix. 133.) - Note to the second edition.

The compound solution has been used in chronic bronchitis, by inhalation, in the form of spray, as produced by the atomizer; from two to ten minims being employed for the purpose to one fluidounce of water.