918

Appendix.

it reduces the morbid irritability of the stomach, and thereby enables the juices ofthat organ to be more slowly secreted and of a more healthy character.' Casesare also on record in which this acid has proved serviceable in the treatment ofpainful and difficult menstruation, floodings, hemoptysis, and nervous diseases.It certainly is a very powerful sedative; and may be employed in all cases, inwhich sedatives and narcotics are indicated, with decided advantage.

Asa local remedy, Prussic acid is the only application which can be depended orefor allaying the itching and tingling which are so distressing in impetiginous affec-tions. I liave lately employed it with unvarying success in these complaints, andhaving published my observations, - I am in hopes of seeing its value determinedin the hands of others. I have found it useful, also, in combination with smaltdoses of oxymuriate of mercury in acne rosacea, and several other cutaneousdiseases.

The dose of Prussic acid is from mij- to iiiviij. It may be administered indistilled water, or in almond emulsion, or in infusion of cinchena bark, as circum-stances may require. When an over dose has been taken, its deleterious effectsare best counteracted by hot brandy and water, and the ammoniated tincture ofiron. As a local application, it may be used in the form of lotion, in the propor-tion of a fluid drachm to a fluid ounce and a half of distilled or of rose water; oras a cataplasm composed of crumb of bread, soaked in a solution of fjjss. of theacid in f Jj. of distilled water.

Although the instantaneous power of Prussic acid, in destroying animal life,when it is taken in doses sufficiently large to operate as a poison, may, perhaps,always prevent medical art from proving beneficial in such cases; yet it isof importance to be able to ascertain in judicial enquiries, relative to suicide or tomurder, that Prussic acid has been administered as a poison. The following meanspointed out by Dr. Granville, for detecting its presence in the animal systemafter death, should be known. Collect the blood contained in the ventricles of theheart, a portion of the contents of the stomach, and of any fluid that may be foundin the head, the chest, or the abdomen, agitate the mixture for some time withdistilled water, and filter the liquid, taking care to preserve the whole at a lowtemperature. To a small quantity of the filtered liquid add a few drops of a solu-tion of pure potass in alcohol; then add a few drops of a solution of sulphate ofiron ; and if a reddish precipitate of the colour of burnt Terra Siena now fall down,which on the addition of a little sulphuric acid, changes to a bAuisb green, andgradually, on exposure to the atmosphere, becomes a beautiful blue, we may coifc-clude that the death of the individual has been occasioned by Prussic acid.

No. V. IODINE.

This substance is procured by first lixiviating powdered kelp with cold water jthen evaporating the ley till a pellicle forms, and setting it aside to crystalize. Onseparating the crystals, the mother water is to be evaporated to dryness, and to themass, put into the flask of an alembic, is to be added half its weight of sulphuric acid,and the same weight of black oxide of manganese ; and, after adapting a capitaland receiver to the flask, the mixture is to be distilled with a gentle heat, as long asviolet vapours arise, which condense chiefly in the capital, in the form of opaque crys-tals, with a metallic lustre. These are Iodine. Various other methods have beenemployed for procuring Iodine, the best is the following, proposed by Dr. Ure. Take

1 Dr. Elliotson has published a small volume containing the result of his prac-tice with Prussic acid in dyspepsia; and has stated that accident led him to try thepowers of the medicine in this class of diseases. Respect for my own characterobliges me to say, that nothing could surprise me more than this statement of Dr.Elliotson; as he acknowledges having read the first edition of Dr. Granville'sTreatise, which contains a letter from me, dated 20th February, 1819, stating my»entiments of the utility of Prussic acid, in dyspepsia, and th« modus operandiof the remedy, previously to his having employed it!

- Vide Medical and Physical Journal. Feb. 1822.