Complex sentence: Collinson was responsible for surveying the approaches to Chapoo, and once the troops were landed, Bate accompanied them, earning a Mention in Despatches from Vice Admiral William Parker who commanded the force.
Split into simpler sentences: Collinson was responsible for surveying the approaches to Chapoo, and once the troops were landed, Bate accompanied them. This earned him a Mention in Despatches from Vice Admiral William Parker who commanded the force.