Complex sentence: Goldsmith Andrew Drummond (1688--1769) founded the bank n 1717 and the bank remained within the Drummonds family until 1924 when the bank was purchased by The Royal Bank of Scotland.
Split into simpler sentences: Goldsmith Andrew Drummond (1688--1769) founded the bank in 1717. The bank remained within the Drummonds family until 1924 when the bank was purchased by The Royal Bank of Scotland.