“…After reviewing the von Fellenberg procedure, as well as several of its modifications (Aitkin (15,16), Leitch and Henderson (17), Closs (18), Veil and Sturm (19)), he concluded that no modification of von Fellenberg's method would prove satisfactory for two reasons: 1) iodine is lost during the heating in an open crucible, and 2) the technique is extremely difficult and cumbersome. Von Fellenberg himself recognized the necessity for improvement, as is manifest by his publication of a modified method in 1930 (20).…”