nauseous, even in the smallest quantities. A drop of prussic acid fills a whole room with its bitter aroma. But arsenious acid is tasteless and odorless, and so unsuspicious to the most wary animals that its name has become a synonym of ratsbane. The reason is apparently this: that Providence (or "natural selection") has endowed animals with a protective antipathy against all poisons they could possibly mistake for comestibles, but not against such out-of-the-way things as arsenic or sugar of lead, nor against the mixtures by which the art of man has disguised the taste of naturally unpalatable substances. Coffee, without sugar and milk, "straight and strong," as the Turks drink it, would hardly tempt a Christian schoolboy; mixed, it can be made seductive enough to deceive even the ex-officio opponents of the stimulant-habit. In such commixtures as milk-punch, beer-soup, "Scutari sherbet," the taste—though not the effect—of alcohol almost disappears; the Algeria trappers catch monkeys with a mélange of rum and manna-sirup. A famous cook of the "Frères Provençeaux" used to boast his ability of compounding delightful ragouts from meat in any state of decomposition. Early habits and the influence of evil examples also tend to corrupt the integrity of that physical conscience whose arbitrations form the health-code of our dumb fellow-creatures. In large cities the panders of vice vie in the art of making their poisons attractive, and, where such dangers can not be avoided, it is always the safest plan to meet and master them in time.
Early impressions are very enduring, and can make useful habits as well as evil ones a sort of second nature. In order to forestall the chief danger of in-door life, make your children love-sick after fresh air; make them associate the idea of fusty rooms with prison-life, punishment, and sickness. Open a window whenever they complain of headache or nausea; promise them a woodland excursion as a reward of exceptionally good behavior. Save your best sweetmeats for outdoor festivals. By the witchery of associated ideas a boy can come to regard the lonely shade-tree as a primary requisite to the enjoyment of a good story-book. "Or, mes pensées ne voulent jamais aller qu' avec mes jambes," says Rousseau ("Only the movement of my feet seems to set my brains a-going"), and it is just as easy to think, debate, rehearse, etc., walking as sitting; the peripatetic philosophers derived their name from their pedestrian proclivities, and the Stoic sect from their master's predilection for an open porch. Children who have been brought up in hygienic homes not rarely "feel as if they were going to be choked" in unventilated rooms, and I would take good care not to cure them of such salutary idiosyncrasies.
Every observant teacher must have noticed the innate hardiness of young boys, their unaffected indifference to wind and weather. They seem to take a delight in braving the extremes of temperature, and, by simply indulging this penchant of theirs, children can be made weather-proof to an almost unlimited degree; and in nothing else can