I’ve always loved the way that the mausoleum for Sir Francis Bourgeois and Noel Desenfans is integrated into, and central to, the experience of their picture gallery, so that one breaks off from looking at Claude and Poussin and steps into the amber gloom of their burial place.   Soane was already a friend of Bourgeois when Bourgeois died in 1811.   They had both been opponents of Benjamin West as President of the Royal Academy and both were ardent freemasons.   So, the design of the picture gallery and mausoleum was a labour of love, making use of Soane’s deep knowledge and love of Roman funerary buildings: