Our name "Trefzger" has always been difficult to pronounce and to spell. "Trefsgar" and "Trefsger" are much simpler than "Trefzger".
The 1860 Federal census spells the Martin's name "Trefhisher".
The 1870 Federal census spells the Martin's name "Yrasker".
The 1880 Federal census spells the Martin's name "Trefsger".
Bertram's Civil War records spell his Bertram's name "Trefskar" and "Trefsker".
Anthony"s Civil War records spell his Anthony's name "Trefsker" and "Trefsger".
Bertram's tombstone reads "Bertam Trefsker".
It is true that everything was done in longhand in the 1800s. It would be very easy to think a Z was an S. And to change an E to an A.
It is interesting that all of Martin and Katherine's children do not spell their names "Trefzger".
Considering the fact that:
1. Frans Joseph Trefzger was involved in the revolution in Baden.
2. Franz Joseph, Martin and his family "left their homes in the middle of the night, crossed the Rhine, and got passage on a ship to America".
3. "Sometime afterward, someone wrote to his family and said that he had died so that the government would not harm his family".
I believe that the change of name to "Trefsgar" and/or "Trefsger" was a deliberate attempt to conceal or hide and protect the family.