The postmark, "Basco, Ill April 18 '78," is handwritten. I'm not certain if Basco didn't have a stamp or if it was just easier to write instead of using it.
I've written about this postcard before, but I just got to thinking about what type of "residential evidence" this gives for both Johann Ufkes (the writer) and Hermann Harms (the recipient). The only thing this card provides direct evidence of is that Johann was at the Basco post office in 1878. There's no address for him on this card and just because he mailed it from Basco does not mean he necessarily lived there.
And Herman may (or may not) have been a resident of Tioga (Tioka) at all. He could have easily just have been a short term resident in 1878--or it simply could have been that in 1878 Johann believed Herman lived in Tioga.
It's always worth your while to think about just what a document provides evidence for and what it does not provide evidence for.