This black and white photograph shows an original design drawing of the exterior east front (or rear) and apse of Wesley's Chapel (1778).
The building was designed by George Dance the Younger (1741-1825) who, at the time, was the Architect and Surveyor to the Corporation of London and responsible for the design of public buildings in the City of London. It was the same office Christopher Wren had held a hundred years or so before Dance, during which time Wren designed the City Churches.
The design drawing shows clearly a neoclassical frieze with classical swags, a motif mirrored in the original entrance portico of the Chapel. Also, columned balustrades were planned for the apse windows and a (triangular) pediment above the apse area. None were carried out so the Chapel, in Wesley's words, became 'neat but not fine'.
The original drawing is in the Guildhall Library, London. See also the photograph of the original drawing of the west (entrance) front of the Chapel in the Online Collection, 2008/11488/5.