Complex sentence: George was promoted in 1812 to be enginewright at Killingworth Colliery with a salary of £100 per year; he built his first steam locomotive, "Blucher", in 1814, and the following year was earning £200 a year.
Split into simpler sentences: George was promoted in 1812 to be enginewright at Killingworth Colliery with a salary of £100 per year. In 1814 George built his first steam locomotive, "Blucher", and the following year was earning £200 a year.