Mary Beale was an English portrait painter. Along with Joan Carlile and Susan Penelope Rosse, she was part of a small band of female professional artists working in London. Beale became the main financial provider for her family through her professional work – a career she maintained from 1670/71 to the 1690s. Beale was also a writer, whose prose Discourse on Friendship of 1666 presents scholarly, uniquely female take on the subject. Her 1663 manuscript Observations on the materials and techniques employed "in her painting of Apricots", though not printed, is the earliest known instructional text in English written by a female painter. Praised first as a "virtuous" practitioner in "Oyl Colours" by Sir William Sanderson in his 1658 book Graphice: Or The use of the Pen and Pensil; In the most Excellent Art of PAINTING, Beale's work was later commended by court painter Sir Peter Lely and, soon after her death, by the author of "An Essay towards an English-School", his account of the most noteworthy artists of her generation.