Complex sentence: In 1875 Balliol historian Arnold Toynbee paid the first of many visits to Whitechapel, and in 1877, Barnett, who kept in constant touch with Oxford, formed a small committee, over which he presided, to consider the organisation of university extension in London.
Split into simpler sentences: In 1875 Balliol historian Arnold Toynbee paid the first of many visits to Whitechapel. In 1877, Barnett, who kept in constant touch with Oxford, formed a small committee, over which he presided, to consider the organisation of university extension in London.