Complex sentence: In the early 1870s W: m Crichton & Co. employed 400 people; most of the products were steam engines and other machinery, and just 30% of turnover came from ships.
Split into simpler sentences: In the early 1870s W: m Crichton & Co. employed 400 people. Most of the sales came from steam engines and other machinery, and just 30% of turnover came from ships.