cent. may be used. In inflammatory infections of the ear, nose and throat, 5 to 40 per cent. solutions are used; for irrigating sinuses 2 to 5 per cent.; for inflammatory conditions of the eye and conjunctival infections in strength of 10 to 40 per cent.; in acute anterior urethritis, as an abortive measure, 20 per cent.; for posterior urethritis or in the routine treatment of anterior urethritis, 10 per cent.; in the genito-urinary tract of the female, from 10 to 50 per cent. Solutions of neo-silvol are prepared by adding the substance to the required amount of water and agitating the mixture until solution occurs.

Neo-silvol is prepared by heating freshly precipitated Ag2O with gelatin (which has been previously dissolved in a dilute alkaline solution) until the Ag2O has been reduced to metallic Ag in a colloidal state of subdivision. The solution is treated with I, which combines with the Ag. The liquid is then evaporated to dryness in vacuo. The finished product contains from 1 to 3 per cent. of combined I in excess of that required for combination with the Ag. Neo-silvol occurs as pale yellow granules. In concentration up to 50 per cent. it forms with water almost colourless, milky or opalescent solutions (colloidal suspensions). Neo-silvol is insoluble in fixed oils, but slowly soluble in glycerin. Solutions of neo-silvol are not precipitated in the cold by strong acids nor by NaCl. If a solution of neosilvol is treated with a solution of KOH no precipitate of AgI is formed; if this solution is boiled for a few minutes, it darkens gradually, but no precipitate is formed unless it is allowed to stand for some time. If a solution of neo-silvol is treated with dilute HCl, AgI is not precipitated; if this mixture is now boiled the AgI is gradually precipitated. Dilute solutions of neo-silvol do not discolour in sunlight (absence of AgCl and AgBr). Transfer about 1 Gm. of neo-silvol, accurately weighed, to an 8-ounce Erlenmeyer flask containing 100 c.c. water and heat on steam bath until "solution" is effected. Add 5 c.c. of HCl and boil gently over a flame for 10 or 15 minutes; cool, and filter through a tared Gooch crucible containing a fairly thick pad of asbestos. Wash thoroughly with water acidulated with HCl 0.3 per cent. Dry at 100° C. and weigh as AgI. (The weight found is equivalent to 18 to 22 per cent. of AgI.)

Novocain Base, Characters and Tests for. (New and Nonofficial Remedies, through J. Amer. Med. Assoc., 1922, 79, 1519.) -Procaine Base-Para-amino-benzoxydiethylamino-ethane.

Actions and Uses.-The same as those for procaine. of its solubility in oil it is suitable for an oil spray. cent. solution in expressed almond oil may be used. Dosage. The same as that for procaine.

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Because A 10 per

Characters and Tests.-Novocain base occurs as a white, odourless, granular powder; permanent in air; insoluble in water; soluble in EtOH, Et2O, CHCl, and C.H.; also soluble in fixed and volatile oils. Novocain base melts at not below 61° C. Dissolve about 0.1 Gm. of novocain base in 1 c.c. of H.SO. The solution is colourless (organic impurities). The solution of the base, dissolved in 2 per cent. HCl, should respond to the tests for procaine. Ash not to exceed 0.1 per cent.

Ointments, Valuation of Certain. E. Collard. (Répertoire Pharm., 1922, 34, 257.) Boric Acid Vaseline.-Two or 3 Gm. of the ointment is placed inside a double counter-poised filter, in an extraction tube, over a tared flask fitted to an upright condenser. The extraction is performed with 30 Gm. of benzin on the water-bath, and is complete in about 30 minutes. The double filter is then dried at the normal temperature to constant weight, the benzin being allowed to evaporate spontaneously since there is a risk of loss of HBO, if heat be employed to dry the residue, which is weighed when constant. The flask may be fitted to an ordinary condenser and the solvent distilled off. The residue is then weighed as vaseline. The sum of the two weights, HBO, and vaseline, should be approximately that of the original weight of ointment taken. The same method is applicable to most ointments containing an active ingredient insoluble in benzin, in a fatty basis. It is found to give satisfactory results with zinc ointment, lead iodide ointment, strong mercurial ointment, and the 33 per cent. HgCl ointment, which is not yet official. In the case of mercurial ointment, the precaution must be taken to use filter-paper of good quality, otherwise the finely divided Hg may pass through the inner filter. This method is recommended for official recognition. (See also Y.B. 1922, 302.)

Orange Flower Ointment. (Spatula, through Pharm. Zentralh., 1922, 63, 316.) White wax, 45; spermaceti, 45; coconut oil, 30; oil of sweet almonds, 30. Melt together, then incorporate orange flower water, 30; simple tincture of benzoin, 3.

Percolation, Hot, Apparatus for. R. Bordier. (L'Union

Pharm., 1922, 63, 290.) The cylindrical percolator (1) containing the substance to be extracted (6) placed on a plug of glass wool (5) is fitted into a larger cylinder forming a water jacket. This is connected with a flask completely filled with water (2) by means of two bent tubes. This flask is immersed in a water-bath (3), fitted with a constant water-flow and a thermostat. The water in the filled flask can thus be heated to any desired tempera

ture, indicated by the thermometer (9) in the water-jacket, and acts as a thermosiphon. The desired temperature once adjusted the apparatus works automatically. It is specially useful when using inflammable volatile solvents, since the source of heat may be some distance away, and further protected by a metal screen.

Petroleum Emulsion, Note on. A. McCutcheon. (Pharm. J., 1923 [4], 56, 365.) The following emulsion, which is widely

prescribed in Scotland, is found to vary greatly in appearance and consistence when compounded by different dispensers : Paraffin liq., Mxx.; sod. benz., gr. 1; calc. hypophos., gr. 1}; pulv. acacia, grs. x.; pulv. tragacanth, gr. ; ol. amygd. ess., m.re; aquam. chloroform, ad. 3i. Mitte., 3iv. Sig., 3i. before meals. Liquid paraffin varies greatly in sp.g. and viscosity. In making this emulsion, therefore, it is important to employ a liquid paraffin which not only corresponds to the official sp.g., but is also of high viscosity. To make such liquid paraffin into a proper emulsion it is necessary to overcome the high viscosity during the process of emulsification. Otherwise it cannot be divided up into the minute globules which are the first essential in a good emulsion. To secure this the measured quantity of liquid paraffin, in a suitable container is heated in a water-bath to about 50° C. Place the powdered acacia and tragacanth gums in a warmed mortar and mix thoroughly. Dissolve the NaCH,O, and the Ca(PH2O2)2 in the CHCl, water in a glass measure. Triturate the warmed liquid paraffin with the gums in the mortar, then add all at once the chloroform water solution of the salts, and triturate vigorously until emulsification is complete. Pour the emulsion into the bottle, allow to cool, add the essential oil of almonds, and shake thoroughly. In this way a permanent, uniform, creamy emulsion is obtained.

Pharmacy, Practical Notes on. G. E. Ewe. (Pract. Drug., 1922, 40, No. 12, 22, through Chem. Abstr., 1923, 17, 449.)

Colour of Ointment of Red Oxide of Mercury. This ointment when made in modern ointment milling-machines, is yellowish in colour instead of red, because of the high state of subdivision of the oxide. This in no way detracts from its value. In fact, the minute subdivision of the oxide is desirable, especially where the ointment is intended for application to the mucous membranes.

Proportion of Acetic Acid required for the Preservation of Acetic Fluid Extracts.-Acetic fluid extracts of larkspur, sanguinaria and squill require between 7 and 8 Gm. of absolute AcOH per 100 c.c. for preservation, although fluid extract of sanguinaria has kept well with as little as 4.06 Gm.

Variation of Tinctorial Power of Sanguinarine Nitrate.-The cause for the variation in colouring power of this material is thought to be due to contamination with varying amounts of the "purple substance," which is a normal constituent of sanguinaria.

Behaviour of SrCO, upon Ignition.-SrCO, can be ignited with the filter paper on which it is collected without the formation of oxide providing an ordinary "blast Bunsen burner" which is not equipped with artificial air pressure is used. Ignitions show the same weight before and after treatment with (NH),CO3. Hazards of the Manufacture of Emetine Salts.-Workers engaged in the manufacture of emetine salts frequently suffer from boil-like eruptions due to the irritant action of the alkaloid. These eruptions usually occur at the entrance of the nasal passages, the wrists and neck. They yield to treatment with the common antiseptic healing ointments.

Phenoltetrachlorphthalein. (New and Non-official Remedies: J. Amer. Med. Assoc., 1923, 80, 1218.) A dibasic dye formed by the condensation of phenol and tetrachlorphthalic acid or its anhydride. It differs from phenolphthalein in that four Cl atoms have been replaced by four H atoms.

Actions and Uses.-Phenoltetrachlorphthalein has been used for the determination of the functional activity of the liver. It can be used, in form of the sodium salt, intravenously; it cannot be given subcutaneously or intramuscularly. It has been proposed that the excretion can be determined by the excretion of the drug in the stool, or by the excretion of the drug in the duodenum by means of a duodenal tube, or by its disappearance from the blood stream.

Dosage. From 0.05 to 0-4 Gm. administered in the form of the disodium salt. The solution must not be exposed unduly long, as the salt is sensitive to the action of the CO2 of the atmosphere.

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Phenoltetrachlorphthalein is a pink odourless powder, permanent in the air; practically insoluble in water; very soluble in acetone; soluble in EtOH, Et.O and glacial HC2H2O2; slightly soluble in CHCl3, CH, and CS,. It dissolves in solutions of the alkalies and carbonates to form solutions which are deep purple when concentrated, but which change to violet-red on dilution, and in very dilute solutions assume a bluish tint (distinction from phenolphthalein). Phenoltetrachlorphthalein does not melt when heated to 300° C. It does not respond to the U.S.P. test for heavy metals as described under phenolphthalein. The loss on drying at 115° C. is not more than 0.5 per cent. To about 5 Gm. of the substance, accurately weighed, add 25 c.c. of N/NaOH, heat to about 70° C. and stir. Dilute with warm