Abstract: A tracheal tube assembly comprises an outer tube and an inner cannula that is insertable within and removable from the outer tube. The inner cannula has an inner surface of a flexible plastic material such as PVC to which respiratory secretions cling. The outer surface of the cannula is of a material having a lower friction than the inner surface and may be a helical filament or a continuous layer. The machine end of the inner cannula projects beyond the outer tube to form a flexible portion which is terminated with a coupling.

Abstract: A method of setting hair which comprises treating the hair with an aqueous solution of a metal S-thiosulphato-derivative, and curing the derivative. The hair is treated at temperatures of from 15.degree.-60.degree. C. with aqueous solutions containing Bunte salt derivatives, covered with impermeable material, and left to react at from 20.degree.-60.degree. C. before finally rinsing off with water. The permanent setting is as good as with conventional thioglycollate compounds, but the noxious smells associated with the latter are absent.

Abstract: A water soluble glass article suitable for treating a diet deficiency in a ruminant animal. Animals are treated by lodging in the reticulo rumen an article containing(a) P.sub.2 O.sub.5(b) R.sub.2 O where R is chosen from Na, K and Li(c) at least one other glass forming or modifying material, usually CaO, MgO or Al.sub.2 O.sub.3(d) at least one deficiency-rectifying element selected from Cu, Se, Co, Zn, I, Mn and Mg.In the composition the sum of P.sub.2 O.sub.5 and R.sub.2 O is not less than 56 mol %, and not more than 76 mol % if CuO and/or ZnO are present or not more than 92 mol % if CuO and/or ZnO are absent and one or more of CoO, SeO and I is present. If CuO and/or ZnO is present then the amount of each of P.sub.2 O.sub.5 and R.sub.2 O (preferably present in substantially equimolar amounts) does not exceed 45 mol %.

Abstract: A process and plant is provided for the production of nitric acid from atmospheric air in which the feed air is passed in succession through a number of stages each comprising a high temperature regenerative nitrogen fixation reactor followed by a catalytic oxidation reactor and a nitric oxide absorber, all operating at superatmospheric pressure. Heat is exchanged between the inlet and outlet gas streams of each stage absorber. The compressors are driven by a turbo-expander powered by the exit gas stream in which fuel has been burned upstream of the turbo-expander. The nitrogen fixation reactors each consist of a pressure vessel enclosing a gas-permeable refractory wall surrounding a furnace chamber in which fuel is burned, the interior of the vessel being divided into two sections by an impermeable wall with a gap for flow through in the furnace zone.