Abstract: The present invention relates to a plasma torch intended for being submerged into a bath of molten metal, such as for example a steel melt. The torch comprises an outer electrode made from a non-consumable material and an inner electrode, where at least the outer electrode is made from a copper pipe having internal channels for circulation of a cooling medium, said copper pipe at least on the outside having a layer of refractory material.The layer of refractory material has a thickness between 1 and 5 mm and is made from Al.sub.2 O.sub.3 or from ZrO.sub.2 stabilized with 5-25% by weight of MgO and/or Y.sub.2 O.sub.3 or oxides of other rare earth elements.

Abstract: This invention relates to new 1,3-dihydro-6-methyl-furo-(3,4-c)-pyridine derivatives of the general formula: ##STR1## wherein, each of A.sub.1 and A.sub.2 represents various hydrocarbon groups, to pharmaceutically acceptable salts of them, to a process for the preparation of said derivatives from the corresponding 6-hydroxy compounds, treated by ethyl bromoacetate and then hydrolyzed. The invention further provides pharmaceutical compositions wherein said derivatives are used as active ingredients. The compounds are useful as diuretics, in lowering blood pressure and as antihistaminics.