William was born around 1840. He married Wilhelmina in March 1868 in New Orleans.  It was her second marriage.
He is listed in 1870 US census with wife and children. His wife Wilhelmina had children by her first marriage with Carl Becker; in this census those children (Frederick, Charles, and Elizabeth) are called Crossman.  He is listed in 1880 US census, New Orleans, Louisiana, living on Esplanade Street with his wife Wilhelmina, and children Margaret Crossman, Mary Crossman, and William Crossman, and her children Fred Becker, Carl Becker, and Elizabeth Becker. The census indicates he was born in Prussia. 
The New Orleans City Directory states that he was a Warehouseman for R.F. Theurer and Sons from about 1871 - 1885. He passed away about 1885.
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