Ammonia Solution of Specific Gravity 0.910: Strong Ammonia Diluted to 24.99 % by Hydrometer (Lunge and Wiernik table, Thorpe 1912)

Old recipes give ammonia by its specific gravity, not by percent. Lunge and Wiernik's table turns one into the other: at 15 C, ammonia of sp. gr. 0.910 holds 24.99 % NH3, 227.4 g in a litre. Strong ammonia is brought to that density with water. Result: ammonia solution of sp. gr. 0.910 at 15 C (24.99 % NH3). Source: Thorpe, Dictionary of Applied Chemistry vol. 1 (1912), p. 139, after Lunge and Wiernik. The dilution is ours. Picture drawn by Youblob.