5 2 onto one of the letter stacking locations sb 1 to sbz when an end location which is assigned a certain destination address is located beneath a letter stacking location which contains a letter with this destination address the letter is transferred from the letter stacking location to the end location if for example the end location er which is assigned the address u201c wendelsteinstr 14 u201d is located beneath the letter stacking location sbk and if a letter with the destination address u201c wendelsteinstr 14 u201d is located in the letter stacking location sbk this letter is transferred from the letter stacking location sbk to the end location er the transfer of the letters from the letter stacking locations sb 1 to sbz to the corresponding end locations e 1 to ey is controlled by a control means 8 as soon as the end location er has reached the arrangement 9 for emptying the end locations this arrangement being provided at the end of the sorting installation the letters and large letters which are located in the end location er are removed there by the arrangement 9 all the end locations e 1 to ey are emptied one after the other with the aid of the arrangement 9 in which case the sorting of the letters b and large letters g which is predetermined by the sequence of the end locations e 1 to ey is maintained the letter stream tb transported by the letter transporting path 5 1 5 2 has already been sorted on a preliminary basis that is to say it has already undergone the first sorting cycle for mail delivery sequence sorting.