[Illustration: (_C._) A Liebig’s Condenser. (The other _reference letters_ are self-explanatory.)] Although a retort is recommended by Liebig for the distillation, and is usually adopted, on the small scale, for the purpose, a flask closed by a cork perforated by two tubes, as exhibited by the _engr._, will be found more convenient and safe; as the product is then less likely to be contaminated by the ‘spirting’ of the ingredients over the brim of the vessel. The heat of a diffused gas-flame may also be often advantageously substituted for a sand bath. _b._ From ACETATE OF POTASH:—— 1. Acetate of potash (fused and powdered) is placed in a still, or other suitable vessel, and 50% of the strongest sulphuric acid (‘oil of vitriol’ of fully 1·84 sp. gr.) being added, the mixture is distilled to dryness, as before. The product is 50 to 51% of the weight of the acetate employed, with a sp. gr. of about 1·0735 to 1·074, containing about 66% of anhydrous acetic acid, or nearly 80% of ordinary glacial acid. By rectification from a little dried acetate of lead a perfectly pure acid of almost any strength may be obtained. The ingredients are nearly in equiv. proportions. _c._ From ACETATE OF LEAD:—— 1. (Ure.) Take of dried acetate of lead, 4 parts; strongest oil of vitriol, 1 part. Distil slowly to dryness. Nearly equal to the last. 2. (Liebig.) Acetate of lead, 3 parts; sulphuric acid, 8 parts; as before. 3. (Dollfuss’ Concentrated Acetic Acid.) Take of dried acetate of lead, 12 oz.; sulphuric acid, 6 oz.; distil 7 ounces. _d._ From ACETATE OF LIME:—— 1. (Christl.) Raw acetate or pyrolignate of lime (prepared by Völckel’s process), 100 parts, is mixed with hydrochloric acid (20° Baumé, or sp. gr. 1·1515), 120 parts; and after 12 hours, distilled in a copper vessel, with a gradually applied heat. The product is 100 parts or lbs. of acetic acid of 8° Baumé (sp. gr. 1·0556), containing about 47% of hydrated acid, only slightly coloured and empyreumatic, fit for various manufacturing purposes. The advantage of this process is the low price of hydrochloric acid, and the product not being contaminated with sulphuric or sulphurous acid. _Obs._ It will be found that pyrolignate of lime generally contains 60% to 70% of neutral acetate; but should it contain either more or less, a proportionate quantity must be employed. When the proper proportions are used the distillate gives only a scarcely perceptible turbid cloud when tested with nitrate of silver. If the hydrochloric acid used has the sp. gr. 1·16, a less quantity being employed, the product will have the sp. gr. of 1·058 to 1·061, and will then contain from 48 to 51% of the monohydrate, or 41 or 42% of anhydrous acetic acid. The resin sometimes found floating on the mixed ingredients should be carefully removed, by skimming, before distillation.