Complex sentence: One method Tufte encourages to allow quick visual comparison of multiple series is the small multiple, a chart with many series shown on a single pair of axes that can often be easier to read when displayed as several separate pairs of axes placed next to each other.
Split into simpler sentences: One method Tufte encourages to allow quick visual comparison of multiple series is the small multiple. This is a chart with many series shown on a single pair of axes and it can often be easier to read when displayed as several separate pairs of axes placed next to each other.