Although the Swiss did not represent a large portion of the immigration to the United States, early correspondence from Switzerland to the U.S. provides interesting opportunities to study transit markings.

Posted Basel, June 24, 1838 to New York

Mailed April 6, 1851 at Frauenfeld, via Zürich (transit mark on reverse), via
St. Louis (Basel) transit mark on lower right dated April 9, via Liverpool red
PAID marking upper right dated April 10, via New York dated April 23. No
arrival marking at New Orleans