Seward, who had completed his five year articles in May 1799 and was to stay as an asistant until 1808, roughly drew out the measurements of the house and church at Port Eliot from 11th to 18th September 1804. Soane was to have accompanied him but became unwell, making his only site visit in the following month. P.Dean (Sir John Soane and the country estate, 1999, pp.103-4) describes the house as '... long and thin, mostly two rooms deep and parallel with the ancient priory church of St Germans, whose monastic remains are partly incorporated in the structure. Two wings extended at its west end with the distinctive 'round room' recently built at the east end of the house by the architect John Johnson [1732-1814 ]'. Seward's fully drawn out site plans and elevations follow (drawings  to ).
To avoid tedious repetition, some facts such as page size, water mark and hand are given here and not repeated under individual catalogue entries. Usually a drawing, whether loose or bound into a volume has an individual number. When cataloguing, drawings are numbered (as far as possible) in the sequence that they were made. So that the first drawings for Port Eliot, which are survey drawings made out of the office in a freehand style in September 1804 are numbered  to . Then follow the survey drawings based on the earlier drawings made on site beginning with drawing . However, there is a difficulty with catalogue numbers for the first group drawing  to  which relates to the recto and verso of a sheet. Here the numbering (bottom right-hand corner) follows that principle but when photographed the recto of a sheet was photographed with the verso of the preceding drawing though in fact some of the drawings do span two pages/sheets in that way.