 The great hour bell , cast by Johann Reber , has remained unchanged since the tower 's reconstruction in 1405 . It has a diameter of 127 centimetres ( 50 in ) , a weight of 1 @,@ 400 kilograms ( 3 @,@ 100 lb ) and rings with a nominal tone of e ' . The inscription on the bell reads , in Latin : In the October month of the year 1405 I was cast by Master John called Reber of Aarau . I am vessel and wax , and to all I tell the hours of the day . 
