^^^^

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I passed at Munic and as you may casily imagine in a veryagreeable manner, though in consequence of having spraincdmy leg I was kept in bed there for nearly a week. Liebigand many other scientific and artistic friends were at home,so that there was no want of rational enjoyments in thebavarian capital. Amongst the curiosities seen there, therewas a specimen of the poisoned chinese bread sent to Liebigfor chemical analysis. He found considerable quantities ofArsenic in it. Of late I (have) worked again a good on myfavorite subject and ascertained a number of facts which seemto me to put beyond doubt the correctness of that old notionof mine, according to which oxigen, such as it exists in theatmosphere, is in a chemical point of view an entirely inertbody and any oxidation being apparently brought about byit, is preceeded by its allotropic change of condition. Theessential oil of bitter Almonds (Benzule) has become to me abeautiful object of research, which substance, being assistedby solar light, enjoys the power of rapidly taking up commonoxigen and transforming it into that State, in which it producesall the oxidizing effects of ozonised oyigen' decomposition ofJodide of potassium, coloring blue the Solution of guajacumetc. Leaving that oxigen associated to the oil, it rather rapidlyoxidized that matter into hydrated benzoic acid. In presentingmy best compliments to Mrs. Faraday and begging you todrop the inclosed into a letter box I am my dear Faraday

Yours

most truly

C. F. SCHOENBEIN.

1 The results of these investigations Schcenbein sums up in a paperentitled: "Über das Verhalten des Bittermandelöles zum Sauerstoff." Basl. Verh.Bd. 2. 1857. p. 3.

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