Task: Question Generation
Input (English): Buckingham Palace finally became the principal royal residence in 1837, on the accession of Queen Victoria, who was the first monarch to reside there; her predecessor William IV had died before its completion. While the state rooms were a riot of gilt and colour, the necessities of the new palace were somewhat less luxurious. For one thing, it was reported the chimneys smoked so much that the fires had to be allowed to die down, and consequently the court shivered in icy magnificence. Ventilation was so bad that the interior smelled, and when a decision was taken to install gas lamps, there was a serious worry about the build-up of gas on the lower floors. It was also said that staff were lax and lazy and the palace was dirty. Following the queen's marriage in 1840, her husband, Prince Albert, concerned himself with a reorganisation of the household offices and staff, and with the design faults of the palace. The problems were all rectified by the close of 1840. However, the builders were to return within the decade.
Output (English): At the end of which year were most of the design problems of the palace rectified under Prince Albert?