Transfering all depends on the makeup of the ink. Some inks will stay somewhat "wet" for a very long time. Researching the inks would be a tremendous undertaking, as the recepies were often considered trade secrets so nothing was published.
An ink based on Linseed oil could in theory never fully dry. Dry to the touch, dry enough for most uses, but never completely dry. I have a stamp printed on similar cardboard to a T206 sometime before 1900. While in transit to me from the UK in 2011 it left a nice transfer on another similar one packed in the same envelope.
Black inks seem to be especially susceptible to that. They're more visible of course, but in addition there are some very technical aspects to black ink in that era that make it interesting. (Varying viscosity based on what form of carbon was used as the pigment, plus a form that varied with pressure in an unexpected way. Huge problems for some sorts of printing around 1873, and the mechanisms weren't well understood till much later. )
Modern inks based on vegetable oil are terrible for not curing and leaving transfers on just about anything for any reason. Read a Sports illustrated on a hot summer day and see how much of it sticks to your fingers.
Steve B
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