Christ Church (Christuskirche)
In it, he bequeathed almost all his possessions to the city of Lahr. He also left precise instructions as to how the funds should be used, however.
Like a mediaeval benefactor, Jamm - not known as a churchgoer during his lifetime - decreed that 250,000 Reichmarks should be spent on the construction of a church "in honour of Christ" right next to his park, today's City Park.
Jamm wished to be laid to rest in this church. Jamm even left strict instructions about the style of construction and the long-term occupation of the pastorate in his will.
As a result, Christ Church was built between 1877 and 1880 as Lahr's second Protestant church.
The result was a domed building in the style of the Italian Renaissance.