NITRO-HYDROCHLORIC ACID.
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parts bitten by rabid animals or venomous serpents, to phagedeniculcers, &c. In order to confine the acid to the spot intended to be actedon, the neighbouring parts may be previously smeared with some resinousointment. In sloughing phagedeena the application of strong nitric acid,as recommended by Mr. Welbank ( Medico-Chirurg. Trans, vol. xi.) isattended with the most successful results, as I have on several occasionswitnessed. The best mode of applying it is by a piece of lint tied rounda small stick or skewer. When the slough is very thick, it is sometimesnecessary to remove part of it with a pair of scissors, in order to enablethe acid to come in contact with the living surface.
Largely diluted (as 50 or 60 drops of the strong acid to a pint or quartof water) it is recommended by Sir Astley Cooper as a wash for slough-ing and other ill-conditioned sores.
In the form of ointment (Unguentum acidi nitrici, Ph . Dub.) it is usedin various skin diseases, especially porrigo and scabies, and as anapplication to syphilitic sores.
Nitric acid vapour has been employed to destroy contagion, but it isprobably inferior to chlorine. It was first introduced for this purpose byDr. Carmichael Smyth (to whom Parliament granted a reward of i'5000):hence these fumigations have been termed Fumigationes nitricce Smythiance.The vapour is readily developed by pouring one part of oil of vitriol overtwo parts of nitrate of potash in a saucer placed on heated sand.
Administration. — Strong nitric acidi nay be administered, in some milddiluent, in doses of from five to ten minims, three or four times daily. Thedilute nitric acid may be given to the extent of thirty or forty minims.
The Unguentum acidi nitrici, Ph. Dub., also calleipommade d’Alyon, oroxygenized fat, is prepared by adding 5J fluidrachms of nitric acid to amixture of one pound of olive oil, and four ounces of prepared hog’s-lard.Binoxide of nitrogen is evolved, showing that the nitric acid is de-composed. Part of the fatty matter is oxidized, and a portion isconverted into eldidine (see Unguentum hydrargyri nitratis ). Thisointment has a firm consistence and a yellow colour. It is more effica-cious when recently prepared.
Antidotes. —Poisoning by nitric acid requires precisely the sametreatment as that by sulphuric acid. (See Sulphuric Acid ).
Ac'idum Ni tro-hydrochlor'icum. — Ni' tro-hydrochlor’ic Ad id.
History and Synonymes. —This liquid was known to Geber ( Inventionof Verity, cli. xxiii.). It was formerly called aqua regia, or nitro-muriaticacid. Its nature was first explained by Davy.
Preparation. — It is readily prepared, according to the DublinPharmacopoeia, by mixing 2 parts, by measure, of hydrochloric acid with1 part, by measure, of nitric acid. In the arts, however, hydrochlorate ofammonia, or common salt, is often substituted for hydrochloric acid; ornitrate of potash for the nitric acid. By the re-action of one equivalentor 54 parts of nitric acid on one equivalent or 37 parts of hydrochloricacid, we obtain one equivalent or 46 parts of nitrous acid, one equivalentor 36 parts of chlorine, and an equivalent or 9 parts of water.
INGREDIENTS USED. RESULTS.
{1 eq. Chlorine . 36j 1 eq. Hydrogen 1* 1 eq. Oxygen . 8
c 1 eq. Nitr s . Acid 46.
1 eq. Hydrochl 5c . Acid 37