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the same experiment in causing the elcctrical brush to act upona piece of paper being impregnated with a Solution of potash.You got salpeter by the electrical ozone, I by ozone beingproduced in the chemical way. In your experiment, as wellas in minc, the formation of nitric acid, is due to a secundarychemical action and not to the immediate or direct Union ofAzote and Oxygen. I think it likely that during the action ofOzone upon the alkaline Solution, not only ozonate of potashis formed, but also ozonide of potassium, just in the same manneras out of Chlorine and potash, chlorate of potash and Chlorideof potassium are produced. It is however a chemical possibilityalso that ozone and potash gencrate nothing" but Ozonate ofpotash. If you wish to repeat my principal experiments I stronglyrecommend to you the use of paper being impregnated withstarch and Jodide of potassium. It is a test for ozone beingfar superior even to the most delicate galvanometer. By thatmeans you will easily asccrtain the disengagement of ozonenear a piece of phosphorus if that body is put into the openair after, having been a little rubbed and dried by filtering paper.Provided the slow oxidation of phosphorus be rather rapid,your test-paper will not fail being turncd bluc in a few instants.At a low temperature no such result will be obtained. Togive you a matter-of-fact proof of the bleaching power ofozone I lay by three stripes of litmus paper 1 of which No. iwas bleached by the electrical brush (produced by a four hoursworking of the machine), Nr. 2 by voltaic ozone and Nr. 3 bychemical ozone. As the lattcr one is in a more CondensedState it bleaches more rapidly than the two other sorts ofozone do.

1 These Strips are however missing. Attached to a letter to Berzelius,<lated April 14A 1844 are three Strips shewing clearly the similarity of thebleaching actions of voltaic, chemical and electrical ozone. In fact one of themis the identical strip with which he for the first time proved the bleaching power ofthe electrical smell. Kahlbaum, Briefwechsel Berzelius-Schcenbein Basel 1898. p. 48.

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