Found this in a stack of Russian items.
The first view is the front of this postal stationery (H&G B-39 issued 1883) postmarked August 13, 1887.

Next image is rear of cover with TPO marking (s). The top two markings are the TPOs. The second word starting with "BA" roughly means "Vagon" or wagon which further translates to railway carriage.
Cancel date August 18, 1887.
NOTE: There appear to be two different TPO markings, the top one and the second one vary by 2 days.
NOTE: Letter flow shows originally mailed 13th, first TPO cancel on the 16th, Moscow cancel on the 17th, second TPO marking on the 18th and finally bottom (receiver) marking on the 19th.
NOTE: Letter has a nice wax seal, but top flattened so no detail visible.

Just thought I would share.