Magendie’s solution is that most commonly used. It is of the strength of sixteen grains of sulphate of morphia to the ounce of water, a few drops of acid being added to dissolve the drug. The solution made after the plan of Dr. H. M. Keyes is excellent. It will keep for a long time unchanged. He writes as follows: “Some years ago, while attached to the Roosevelt Hospital, in New York city, after repeated experiments with various tests and anti-ferments, I became convinced of the practicability of making a solution of the sulphate of morphia, of the strength of Magendie’s, without the aid of acid, except salicylic, and that not as a solvent, but as a preventive of decomposition, making a solution that, when properly prepared, gave perfect satisfaction after years of use, never causing abscesses, as is frequently the case when the mineral acids are used, and when carried in the pocket for months being in as perfect condition for use as when freshly prepared. “The following directions, if followed, will give the desired result:— Sulphate of morphia, 256 grains Salicylic acid, 8 grains Distilled water, 16 fluid ounces. “Heat the water in a porcelain capsule, over a spirit lamp, until the boiling point is reached; add the powders and stir with a glass rod, until they are dissolved. Filter through coarse filtering paper, while hot, and keep in a glass-stoppered bottle of _green_ glass.” Some physicians use carbolic acid, some chloral hydrate, some benzoic acid, and some chloroform, as preservative agents. Any of these substances, present in sufficient amount to prevent decomposition and clouding of the solution with minute vegetable growths, are apt to be irritating. In my first work on morphia, a full list of the solutions used in this and other countries will be found. Erysipelas sometimes results from the subcutaneous use of morphia. The syringe needles are sometimes broken off in the flesh. This is, however, a rare occurrence. The method of making an injection, undoubtedly, has something to do with the occurrence of abscess. The usual plan is to pinch up a fold of skin and pushing the needle in quickly, inject the solution slowly, _beneath_ it. Some persons prefer to plunge the needle deep into the muscular tissue. It is claimed for this plan that abscess seldom occurs, and there is certainly less liability of wounding a vein. The following is taken from my book on “Morphia Hypodermically,” and illustrates very fully another danger sometimes attending the use of the drug in this way:—