How times have changed!
Came across this print of Knotts Green House, Leytonstone residence of Joseph Gurney Barclay, noted astronomer and head of Barclays Bank (yes, that Barclays Bank)…
Knotts Green House - Residence of Joseph Gurney Barclay
The drawing is taken from the Illustrated London News, July 15th 1865. The caption reads “Entertainment Given by Mr Gurney Barclay, at Leytonstone, to the Agents of the London City Mission”. Unfortunately, like most of the great old houses in Leytonstone, Knotts Green (which was situated around the Matlock Road area) eventually fell into disrepair and was knocked down in the 1960s to make way for Livingstone College and subsequently the tower blocks of the Livingstone Estate, also later demolished.
Tragic 
It was probably the Barclay family that my great great aunt worked for – eventually becoming the head housekeeper at perhaps this house (unless they had more than one house in the area). I think another member of the family worked in the gardens, and became a market gardener, and it may have been the Barclays who helped with the education of their brother, who became a missionary. There was a Miss Barclay of Leyton who ran a school in Walthamstow in the late 19th century.
Any idea what their names were? I could check the census records to see which house it was.