Complex sentence: He began to collect classical sculpture in the late 1850s, though he only collected his first major paintings in 1868, at which date Sir John Charles Robinson (1824--1913), former V&A curator, became his advisor.
Split into simpler sentences: He began to collect classical sculpture in the late 1850s. He collected his first major paintings in 1868, at which date Sir John Charles Robinson (1824--1913), former V&A curator, became his advisor.