George in 1759 succeeded to the estates of Mellerstain and assumed the name of Baillie. So we have another George Baillie and it is he who was the builder of Mellerstain. George Baillie had done the Grand Tour and had become imbued with the classical taste. The latest refinement of this taste was, in the second half of the eighteenth century, represented by Robert Adam, the most fashionable architect of his day, and the other sons of old William Adam, who, had already begun to rebuild Mellerstain. George Baillie resolved to employ him for the completion of his house. The exterior shows little trace of Robert Adam’s influence, but the plan of the house with its bold projection of the centre on the north front and the contrasting flat façade to the south, is in his style, and the interior is almost wholly his work. The library with its bookcases and green and white marble mantelpiece is entirely Adam, and the ceiling, dated 1770 is considered to be one of his masterpieces. Another splendid ceiling, dated three years later and decorated with eagles and sphinxes, is in the music room in the centre of the garden front.
More About George Baillie: Fact 1: Changed name to Baillie on inheriting estates of maternal grandfather.
More About George Baillie and Eliza Andrews: Marriage: 1759