Below is an 1824 extract from Ackerman's Repository who published this detailed account of the Earl of Cassillis estate. This appears to be one of the first references to the estate being named St Margarets.
The pictures above by John Gendall were published by Ackerman in 1824. Below is an extract Samuel Leigh's 1829 Panorama of the Thames showing the same property.
Earl Cassillis employed several architects to make improvements to his estate. One of these was Leonard Wild Lloyd who was engaged in various projects with Joseph Todd. The other was an architect named James Donaldson who is mentioned in the 1828 advert above. Donaldson was employed at Culzean Castle in Ayrshire, Cassillis family home in Scotland.
Samuel Leigh's 1829 Panorama of the Thames shows what we believe to be the cottage that Donaldson designed. Shown as the residence of Major Brookes the property was later enlarged and named Cassillis.
Earl Cassillis son John Kennedy Erskine married Lady Augusta Fitzclarence, daughter of Dorothea Bland and the future King William IV.
Below are contempory paintings of King William IV and his daughter Augusta. Augusta is shown with her 3 children; Millicent Anne Mary Kennedy Erskine, William Henry Kennedy Erskine and Wilhelmina Kennedy Erskine.
In 1831 John Kennedy Erskine died. The couple had recently moved into Mrs Bland's old house which was now named Seaton House.
In 1836 Augusta Kennedy Erskine married John Frederick Gordon, after which Seaton House was later known.
Above and below are two early engravings showing Seaton House.
The 1829 land tax extract above shows Earl Cassillis as also owning Mrs Bland's
Below is the Gate Lodge designed by Robert Lugar for St Margarets.
In 1831 Earl Cassillis became Marquis of Ailsa
The above 1840 Tithe map shows Cassllis estate and the land bordering the Thames from Seaton House on the left to the area where The Avenue would be built ten years later.
The index below lists the individuals plots. No. 508 is the main St Margarets mansion and No.512 is the cottage previously occupied by Major Brookes. The cottage formed part of the Cassillis Estate. From 1832 it became for several years the home of Sir Edmond and Lady Stanley. The 1841 census records Anthony Coningham Sterling, a relation of Earl Cassillis daughter Anne Baird.
Above map image courtesy of Hounslow Local Studies
The above illustration is from W B Cooke's 1842 handbook to Richmond and Twickenham.
In 1846 The Marquis of Ailsa died. His wife Margaret, the Marchioness died in 1848.
Following the death of the Marchioness of Ailsa the St Margarets Estate was auctioned and sold to Lord Kilmorey who demolished the main mansion and replaced it with a new building in 1852.
The cottage originally occupied by Major Brookes in 1829 had been considerably enlarged over the years. A gardeners lodge was built in the 1860/70's and after a fire destroyed the main house, the lodge became the principal living area. The property became known as Cassillis House.
Below is Cassillis House photograhed in 1947
The Marquis of Ailsa's daughter in-law Augusta died in 1865.