Dirty stamp marks

You come across them sometimes. Stamps with an imprint of, it looks like, a rubber shoe sole. Naturally, you wouldn't keep such a stamp. It looks dirty. But have you ever checked how such an imprint was created? No, not a shoe sole! It's getting a bit clearer here. A stamp pasted on a, well, what could this be? A fragment of an address card for a domestic parcel. But why such greasy, dirty stamp impressions? In September 1924, it was decided to produce rubber stamps on a trial basis, consisting of an abbreviation of the place name with the addition of a number. The trial was to be applied to address cards of the domestic parcel post service. The reason was that the impressions of the metal date stamps on stamps affixed to parcel cards (model 38) were often unclear and barely legible. This made verification particularly difficult. The trial began on January 15, 1925, at the post offices and branch offices of Amsterdam, The Hague, Rotterdam, and Scheveningen. The post offices, or main offices, received a stamp containing only the letters as an abbreviation of the office name: ASD for Amsterdam, GV for The Hague, RT for Rotterdam, and SV for Scheveningen. The branch post offices had a number. This number was placed after the abbreviation. As examples: ASD 3 was the Linnaeusstraat branch office, later Sarphatiestraat; GV 1 was the Balistraat branch office, RT 12 the Ruigeplaatweg branch office, and SV 1 the Badhuisweg branch office. These stamp impressions were quite different from the dirty impressions of Amsterdam with which I started. In total, ten different types can be distinguished. The rates for sending postal packages in 1925 were simply structured. The maximum weight for a domestic postal package was 5 kilograms. The breakdown was as follows: 0-1 kg: 40 cents; 1-3 kg: 50 cents; 3-5 kg: 60 cents. The express fee was 40 cents. The rates were reduced by 10 cents in October 1926. Therefore, packages were usually franked with 30-cent, 40-cent, 50-cent, and 60-cent stamps of the Wilhelmina type. However, other denominations may also occur to meet the rates. Such as from the 1923 Jubilee stamp series or lower Queen Wilhelmina denominations. The trial with the rubber parcel post stamps lasted only two years. By May 1928, the stamps used in Amsterdam, The Hague, and Scheveningen had already disappeared, while a few stamps remained in use in Rotterdam. But there, too, they were quickly withdrawn. Soon, the complete overview of all offices that used the stamps will be included on the website of the Netherlands Academy of Philately under publications and inventory of postmarks: www.nedacademievoorfilatelie.nlSo, if you come across such a dirty, stamped stamp, don't throw it away! It provides a glimpse into the postal history of that time.