Grant wrote of Trinity College Church: 'With the exception of Holyrood, it was the finest example of decorated English Gothic architecture in the city, with many of the peculiarities of the age to which it belonged'. Grant's sketchbook includes detailed visual records of Trinity College Church, made in the knowledge that it was going to be demolished. In the sketchbook he drew: a floor plan 'drawn from measurement' in 1847; seven exterior views from different angles; and thirteen pages of details from the church, such as columns, capitals, grotesques and coats-of-arms. He recorded that the choir was 90 feet long and the width across the transepts was 70 feet. The floor plan was used as the basis for engraving which was included in the first volume of his Old and New Edinburgh series from the 1880s, which traces the history of Edinburgh through its architecture. Interestingly, this sketchbook does not include any drawings of the hospital buildings, which obviously did not interest Grant as much as the church itself; he discusses the interiors of the hospital buildings in Old and New Edinburgh, but the book only includes partial views of it.