The Gleiwitz 1914 address book lists Julius and Alfred Nothmann as co-ownwers of the Siegmund Nothmann manufactured goods business in Kattowitz. According to jewishgen.org Julius and Alfred were sons of Siegmund.

Sources differ regarding his age:
• as a witness to his niece Flora Nothmann's marriage in January 1893 his age is recorded as 50 years, so born 1842-43.
• as a witness to the marriage of his niece Martha Nothmann to his nephew David Freund in November 1904 his age is recorded as 52 years, so born 1851-52.
A birth date of 1851-52 is unlikely because he has siblings born during this time (although one may be his twin), and he would have been only 15 or 16 years old when he married. I have assumed he was born in 1842.

Both marriage records place him in Myslowitz.