I. Hydrocarbons.

These compounds contain the elements carbon and hydrogen in various proportions, are mostly of vegetable origin, many being obtained by destructive distillation and decomposition of organic matter, and all have different boiling-points, by which it is possible to isolate them when carefully distilled fractionally. They are either gases, liquids, or solids, according to the number of carbon atoms in the molecule: 1-4 - gas, 4-10-12 - liquid, and beyond this - solid; they can all be volatilized without decomposition, are colorless, usually with characteristic odor, neutral, soluble in alcohol, ether, carbon disulphide, insoluble in water, oxidize by exposure, the liquids often becoming solids.

Benzinum Purificatum. Purified Petroleum Benzin, C5H12+C6H14 + . - (Syn., Benzin. Purif., Petroleum Ether; Fr. Ether de Petrole purifie; Ger. Gereinigter Petrolather.)

Manufacture: Purified petroleum benzin (benz(oic) + in - odor somewhat benzoin-like) is a purified distillate from American petroleum consisting of hydrocarbons, chiefly of the marsh-gas series, C5H12 + C6H14 +, and may be obtained by mixing sulphuric acid (6 Ml. (Cc.)) and water (55), adding when cold potassium permanganate (.8 Gm.) and, after it is dissolved, petroleum benzin (100 Ml. (Cc.)) in 4 portions, shaking after each; let stand 24 hours, shaking frequently, decant petroleum benzin and add to it potassium permanganate (.2 Gm.) dissolved in water (24 Ml. (Cc.)) containing sodium hydroxide (.2 Gm.), agitate frequently, repeat washing with water, decant purified petroleum benzin. It is a clear, colorless, non-fluorescent, volatile liquid, ethereal, petroleum-like odor, neutral, highly inflammable, vapor (mixed with air) explosive, insoluble in water, freely soluble in alcohol, miscible with ether, chloroform, benzene, volatile or fixed oils (except castor oil), sp. gr. 0.650, distils at 40-80° C. (104-176° F.). Tests: 1. Evaporate from filter paper 10 Ml. (Cc.) - no greasy stain, no disagreeable sulphuretted odor. 2. Evaporate 50 Ml. (Cc.) - residue .0015 Gm. Impurities: Benzene, pyrogenous products, sulphur compounds - which the process is intended to remove. Should be kept carefully cool, remote from fire, in well-closed containers. Dose, ex-20 (.6-1.3 Ml (Cc.)), emulsion, capsule, on sugar.

Allied Products:

1. Benzinum. Petroleum Benzin, C5H12 + C6H14+, official 1880-1910. - Obtained by subjecting crude petroleum to fractional distillation, when benzin (naphtha), illuminating oils, and a residuum largely composed of paraffin are produced - that part collected at 45-60° C. (113-140° F.) being the once official product. It is a transparent, colorless, diffusible liquid, strong characteristic odor of petroleum, but less disagreeable, corresponding to tests and reactions as above.

Properties and Uses. - Internally - vermifuge; Externally - sedative, anaesthetic, solvent, tapeworm, scabies, prurigo, herpes, favus, sycosis, rheumatism, neuralgia, to relieve itching in urticaria, whooping-cough. Like creosote and phenol (carbolic acid) to restrain fermentation in dyspepsia. Good solvent for fats, volatile oils, resins, caoutchouc, alkaloids, etc.

Petrolatum Liquidum. Liquid Petrolatum. - (Syn., Petrolat. Liq., Liquid Paraffin, Mineral Oil, Liquid (Cosmoline) Vaseline; Br. Paraffinum Liquidum, Liquid Paraffin; Fr. Huile de Paraffine; Ger. Flussiges Paraffin, Paraffinol.)

Manufacture: Liquid petrolatum (L. petra: Gr

rock, + L.

oleum: Gr.

oil - rock oil) is a mixture or liquid hydrocarbons, chiefly of the methane series, obtained by distilling off most of the lighter and more volatile portions from petroleum (a substance found in wells, on surface of streams, and oozing from the ground in Pennsylvania, New York, Ohio, etc.), and purifying the liquid residue - the portion going over at 330-390° C. (626-734° F.) being treated with sulphuric acid, then with caustic alkali, filtered (hot) through animal charcoal, cooled to remove solid paraffins (which crystallize out), collecting and reserving that fraction distilling above 360° C. (626° F.). There are two varieties: 1. Heavy Liquid Petrolatum - viscosity 3.1, sp. gr. 0.828-0.905, at 10° C. (50° F.) not more than opalescent (abs. of solid paraffins); 2. Light Liquid Petrolatum - viscosity 3, sp.

gr.0-828-0.905; at 10° C. (50° F.) not more than opalescent (abs. of solid paraffins). Each is a colorless, transparent, oily liquid, free, or nearly free, from fluorescence, odorless, and tasteless when cold, faint petroleum odor when heated; soluble in ether, chloroform, petroleum, benzin, fixed or volatile oils, insoluble in water, alcohol; dissolves camphor, menthol, thymol, and many other substances. Impurities: Acids, sulphur compounds, carbonizable substances, solid paraffins. Should be kept dark, in well-closed containers.

Preparations. - (Unoff.): Petroxolinum Liquidum, 50 p. c, + oleic acid 28, stronger ammonia water 5, alcohol 15, oil of lavender 2. Petroxolinum Spissum, 20 p. c., -+ white wax 35, oleic acid 32, + .

Petrolatum. Petrolatum, C16H34 +. - (Syn., Petrolat., Petrolatum Ointment, Petroleum Jelly, Petrolatum (Molle) Spissum, Vaseline, Cosmoline, Soft Paraffin; Fr. Petroleine; Ger. Unguentum Paraffinum, Paraffin (salbe) butter.)

Manufacture: A purified mixture of semi-solid hydrocarbons, chiefly of the methane series, obtained by distilling off the lighter and more volatile portions from petroleum, and purifying the residue. It is an unctuous mass, yellowish, light amber, slight fluorescence, even when melted, transparent in thin layers, completely amorphous, free, or nearly free from odor and taste; soluble in ether, chloroform, carbon disulphide, oil of turpentine, petroleum benzin, benzene, most fixed and volatile oils, insoluble in water, almost insoluble in cold or hot alcohol, or cold dehydrated alcohol, sp. gr. 0.820-0.865, melts at 38-54° C. (100-129° F.). Tests: 1. 2 Gm. heated in open dish over flame volatilizes without acrid odor; incinerate - ash .05 p. c. 2. Melt, shake with equal vol, of hot distilled water - latter neutral (abs. of acids, alkalies). 3. Digest 10 Gm. for half an hour at 100° C. (212° F.) with sodium hydroxide 10 Gm. + distilled water 50 Ml. (Cc), separate and supersaturate aqueous layer with sulphuric acid - no oily or solid substance separates (abs. of fixed oils, fats, rosin). Impurities: Acids, alkalies, fixed oils, fats, rosin.

Preparations. - 1. Unguentum Hydrargyri Dilutum, 40 p. c. 2, Unguentum Hydrargyri Oxidi Flavi, 40 p. c.

Unoff. Preps.: Emulsum Petrolati, 22.5 p. c, + expressed oil of almond 22.5, acacia 12.5, syrup 10, tinct. of lemon peel 1.5, water q. s. 100. Unguentum Hydrargyri Oxidi Rubri, 40 p. c, +. Unguentum Resorcinolis Compositum, 25 p. c, +

Petrolatum Album. White Petrolatum. - (Syn., Petrolat. Alb., White Petroleum Jelly, Paraffinum Album, White (Vaseline, Cosmo-line) Paraffin, Refined (Paraffin) Petrolatum; Fr. Vaseline blanc; Ger. Weisses Vaselin.)

Manufacture: Petrolatum wholly or nearly decolorized, being a colorless mixture of hydrocarbons, chiefly of the methane series, obtained by distilling off the lighter and more volatile portions from petroleum and purifying the residue. It is a white, faintly yellowish unctuous mass, transparent in thin layers even after cooling to 0° C. (32° F.), completely amorphous, otherwise similar to petrolatum.

Preparations. - 1. Unguentum Acidi Borici, 85 p. c. 2. Unguentum Hydrargyri Ammoniati, 50 p. c.

Unoff. Preps.: Ceratum Camphoroe, 15 p. c. Ceratum Plumbi Sub-acetatis, 38 p. c. Unguentum Zinci Stearatis, 50 p. c.

Properties and Uses. - Petrolatum in its three forms is a bland, neutral, protective dressing and a substitute for fatty substances in ointments; large doses, mild laxative, soothing internal irritation and inflammation. Liquid form largely used in spray, being a good vehicle and solvent for many medicinal agents, applicable to mucous membranes of bronchi, larynx, nose, throat; also used for lubricating purposes. None becomes rancid, and all are absolutely non-irritating. Workmen employed in its manufacture never are troubled with chronic bronchitis or phthisis.

Allied Products:

1 Bitumen. Bitumen, official 1820-1830. - This was the crude petroleum (L. petra, rock, + oleum) as found in various places (North America, England, Scotland, West Indies) under the names naphtha, petroleum, oleum gabearium, Seneca oil, Barbadoes tar (naphtha), Trinidad pitch, etc. Formerly was used as we now use petroleum; upon distillation have residue left in still, termed solid bitumen or asphaltum.