The Landschaftsbilder definitives could also be used to pay any postage due on underfranked mail. The stamps were affixed to the envelope after the amount due was paid and were then cancelled with a T in a circle.

Now I know that in 1955, some six months before the Landschaftsbilder stamps were invalidated, a new cancellation type was introduced with a large T. These are therefore quite rare on this definitive set. I suppose that the example shown here is the cancellation in use before that new version. The Stanley Gibbons catalogue mentions that from 1954 postage stamps were used in place of postage due stamps, but I have no further information at all. If anybody knows anything about this, I'd love to know.

I just received the latest newsletter of the Helvetia Philatelic Society in Britain with lots of new information (for me) about this set. Like how many cylinders were printed, when they were printed, dates of printing, etc. It's so good to be a member of a specialised society because the wealth of information available to you is unbelievable!