M.G. Nyman - Stavanger

I am trying to get more information on my ancestor's line, circa. 1850 in Stavanger, Norway. All I have is names (type and size) of ships owned, but nothing else. Company name: M.G. Nyman Mathias Gustav Nyman who owned the following: slup <<Ellida>> bark <<Franziska>> skonnert <<Ladegaard>> slup <<Caprice>>, <<Kjøkkelvik>> fregat <<Undine>> jagt <<Argo>> skonnert brig <<Alexander>> galeas <<Caprice>> skonnert brig <<Rask>> was a partner in the following: skonnert brig <<Amazon>> fregat <<Stavanger>>, <<Superb>>, <<Oregon>>, <<Birma>> skonnertskip <<Fides>>, <<Saphir>>, <<Alata>> Johan Erik Nyman who owned the following: skonnert brig <<Alexander>> bark <<Alata>> skonnertskip <<Fri>>, <<Krone>> bark <<Diana>> skonnerskip <<Ideal>>, <<Johanne>> bark <<Edwin & Lizzy>> Any information would be much appreciated. I am most interested in what happened to them and when the Nymans sold (lost) their interest in them. Takk.