Chemical New York Corp., the nation’s sixth-largest...

Chemical New York Corp., the nation’s sixth-largest banking company, said its third-quarter profit rose 23.9% from the same period a year ago. Two other large banking concerns, First Bank System Inc. of Minneapolis and Marine Midland Banks Inc. of Buffalo, N.Y., also reported that their earnings were up 58% and 15.3%, respectively. Chemical attributed its profit increase to gains on the sale of investment securities, strong fees for services, continued growth in foreign exchange trading profits, a change in the New York tax laws and higher net interest income. First Bank System, the nation’s 14th-largest banking company, said the latest performance reflected growth in earning assets and non-interest income. The firm also noted that the period a year ago was relatively weak. Marine Midland, the parent of the nation’s 12th-largest bank, said the rise in its profits was attributable to strong growth in both net interest income and non-interest income, which offset higher operating expenses and a higher loan loss provision in the third quarter.