Note 22 — Chapter VI · TTHE COMPOUNDS OF NITROGEN WITH HYDROGEN AND OXYGEN
George Kamensky translation
As certain basic hydrates form peculiar compounds with ammonia, in some cases it happens that the first portions of ammonia added to a solution of a salt produce a precipitate, whilst the addition of a fresh quantity of ammonia dissolves this precipitate if the ammoniacal compound of the base be soluble in water. This, for example, takes place with the copper salts. But alumina does not dissolve under these circumstances.