Complex sentence: Ackermann was an enterprising man; he patented (1801) a method for rendering paper and cloth waterproof, erected a factory at Chelsea for the purpose and was one of the first to illuminate his own premises with gas.
Split into simpler sentences: Ackermann was an enterprising man; he patented in 1801 a method for rendering paper and cloth waterproof and erected a factory in Chelsea to make it. He was one of the first to illuminate his own premises with gas.