Complex sentence: Demand for metal parts used in textile machinery led to the invention of many machine tools in the late 1700s until the mid 1800s, and it was during this time that iron replaced wood in gearing and shafts in textile machinery.
Split into simpler sentences: Demand for metal parts used in textile machinery led to the invention of many machine tools in the late 1700s until the mid 1800s. After the early decades of the 19th century, iron increasingly replaced wood in gearing and shafts in textile machinery.