Mary Webster was an amateur artist who painted Scottish landscapes and Edinburgh scenes. Her surviving watercolours date from the first half of the 19th century. It is thought she exhibited at the RA and the RSA, latterly from an address in England although genealogical research has proved inconclusive.

The image shown here is a watercolour: 'Glen Sannox, Isle of Arran' (credit: Capital Collections).

Reference:

https://www.capitalcollections.org.uk/view-item?i=455&WINID=1615310823672