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Temps de résolution pour ce puzzlePhotoThe first "friction match" was invented by English chemist John Walker in 1827. Early work had been done by Robert Boyle in the 1680s with phosphorus and sulfur, but his efforts had not produced useful results. Walker discovered a mixture of antimony sulfide, potassium chlorate, gum, and starch could be ignited by striking against any rough surface. Partager ce casse-tête | Puzzles récentsJeu Three Tulip VasesMer Boxes and WrapingMar Holiday SceneLun Star ChocolateDim Winter Solstice DeerSam Bear Hed HatVen Squirrel Falling Snow Autres puzzles précédents | |
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