Distilled Water
pure water obtained by distillation, H₂O. The water, if it contains suspended impurities, should be first filtered. The soluble impurities are either volatile or fixed. Of the water which comes over first about one-tenth should be rejected, as it contains nearly all the volatile impurities. The worm should be of block tin, silver, or platinum, as steam acts on glass, dissolving out alkaline silicates. Care should be taken to prevent the mechanical spurting of the liquid; one-tenth of the water should be left in the retort; the solid impurities are also left. It should be redistilled to get rid of traces of organic matter, after it has been treated with a little caustic potash and permanganate of potassium, to oxidize the organic impurities. If it still contains traces of ammonia it should be again redistilled over KHSO, to fix the ammonia. Distilled water is used in chemical analysis, and ought always to be used in preparing medicines.
DISTINGUISHED SERVICE ORDER, an order instituted by Queen Victoria on Sept. 6, 1886, for the reward of na-