Type I postmarks were in use for all cities and towns before the 1935-51 issue came along. Some small towns and small cities kept these type I postmarks as late as 1943. The majority of the small towns that are found to have kept these old postmarks changed over by 1939. Below left is a detail of a Tancacha CB small town type I postmark, and I show the entire cover it comes from at the bottom of the page. Below right is a single of the 20c Juan Martin Guemes, 20cJMG1E, with a C (Cruce) del Uruguay type 1 postmark. In some cases a single digit is used for the year, such as the case below left, where the 8 means 1938, and in other cases two digits are used, such as 38 for 1938 below right. The year digit is often weak, as is the case for the 20cJMG1E below, and these postmarks are difficult to date even when we come across a nearly complete impression.