409,871. Alkali metal carbamates. MATHIESON ALKALI WORKS, 250, Park Avenue, New York, U.S.A.-(Assignees of Cunningham, G. L., MacMullin, R. B., and McCready, W. K. ; Niagara Falls, New York, U.S.A.) Feb. 24, 1933, No. 5738. Convention date, March 31, 1932. [Class 1 (iii).] Sodium carbamate is obtained by reacting sodium bicarbonate with anhydrous liquid ammonia or aqueous solutions of ammonia containing at least 35 per cent by weight of NH3, say 75-90 per cent by weight. Crude sodium bicarbonate from the ammonia soda process may be so treated. Temperatures of -34 C. or higher may be employed. At higher temperatures the reaction must be conducted under pressure. The Specification as open to inspection under Sect. 91 describes the process as applicable to the production of other alkali metal carbamates, e.g. potassium. This subject-matter does not appear in the Specification as accepted. Reference has been directed by the Comptroller to Specification 336,206, [Class 1 (iii)].