Complex sentence: The Lighthouse Board hoped the construction would be completed by the end of 1888, but an additional $10,000 was needed, and the lightstation was not completed until August 1,1889.
Split into simpler sentences: The Lighthouse Board hoped the construction would be completed by the end of 1888. However, an additional $10,000 was needed, and the lightstation was not completed until August 1,1889.