A remarkable series of letters survive charting the commission and execution of her most impressive surviving portrait in oils, the spectacular depiction of Dr Messenger Monsey now in the collection of the Royal College of Physicians in London.[4] Monsey was a physician and companion to Francis Godolphin, 2nd Earl of Godolphin, Mary Black’s portrait dates from 1764 when he was already seventy years old. In a series of letters between Monsey and his cousin, Dr James Monsey of Rammerscales, considerable light is thrown on Mary Black and her aspirations. The initial commission was from both cousins, Mary Black was asked to paint portraits of each of them and copies of the portraits which they could then exchange. Monsey initially ‘liked and encouraged her ingenuity’ but she was expecting to be paid a price commensurate with her training, and proportionate to the prices charged by male contemporaries. Monsey wrote to his cousin, who had returned to Scotland: 

‘I have talk’d to Miss Black about the picture & copies. She does not seem satisfied with the Prices, which I did not take very well & told her so as gently as I cou’d – she said she was in hopes to have had ½ Reynolds price, that he wou’d have had 50l for one of that size, which I told her was 5 times more than He deserv’d, then she said she hop’d she might a ¼ part but she would be satisfied with what ever I thought proper, but I did not care to make myself an estimator of others labours – in short I don’t know how at all to manage between you but I think at all events if I were you I wou’d have no copies for she will by no means be pleas’d to do ‘em at 5g a piece I presume for she hints to me there is very less labour & time in a copy than an original.’[5]

Mary Black’s unreasonable expectation to be paid a quarter of what Joshua Reynolds was then charging for his portraiture seems to have infuriated the Monseys. Dr James Monsey replied: 

‘I am sorry to find Miss Black is grown so saucy, as it will only embarrass, or stop the progress of her reputation and improvement… She will not get a Mounsey every day to sit like inanimate blockheads more to encourage her than for any necessity we had of her Labours. I saw you like and encouraged her ingenuity: I was desposed the same way. She has merit in the picture and I think I have some also, for I assure you I would not set in the same way to Reynolds if he would paint me for nothing.’[6]

The finished portrait demonstrates what an impressive technician Black was. The magnificent pink suit, play of textures and characterful head all demonstrate that she was a powerful portraitist. But the Monseys’ response to her suggestion of adequate remuneration underline the difficulties women faced attempting to operate professionally within a male dominated commercial sphere. Mary Black did exhibit three pictures at the Society of Artists at the end of the 1760s, where she was listed, like her more famous female colleague Katherine Read, as a ‘crayon painter’.

The present work, Portrait of young lady, was one of these exhibits, shown at the Society of Artists in 1768. It was seen in the exhibition by Horace Walpole who annotated his catalogue with the information that she held 'a black dog in her hands' and it was on the basis of this information and the stylistic similarities with a mezzotint depicting Miss Drummond, that Neil Jeffares identified the present work with Mary Black.[7] The same work was subsequently listed in F. Walford, A short memoir of Miss Mary Black, an accomplished artist as: 'A Hampshire Peasant Girl with a Black Dog, Life size, three-quarter length, in crayons.’[8] This raises the possibility that the pastel is not a portrait, but a subject-picture, of the sort that were popular on the walls of the new exhibiting societies. Black’s bravura pastel depicts a beautiful young girl, dressed in white and wearing a pink hat, tied with a pink ribbon, she is holding a black dog. The ‘Peasant Girl’ could be read as a ‘Fancy Picture’. This ambiguous category was described by Martin Postle as: ‘among the most original, popular, and self-consciously modern art forms to have emerged in Britain during the eighteenth-century.’[9]

As Neil Jeffares has noted the handling of the present work recalls the ‘luminous treatment of flesh’ present in the work of the professional pastellist Katherine Read.[10] The use of pastel is skilled suggesting she was highly trained in the medium. Black’s attempt to establish herself as a professional painter were largely unsuccessful. She instead fell back on the more accepted female role, becoming a celebrated teacher, with a large circle of aristocratic and royal clients. Henry Angelo claimed that Black taught the daughters of George III.[11] In his Life of Sir Joshua Reynolds, James Northcote noted: 

'Miss Black was at this time an eminent teacher of crayon painting amongst the ladies of quality, who frequently brought their performances for Sir Joshua’s inspection; and I have heard him observe of Miss Black’s scholars, that their first essays were better than their last. Implying that Miss Black’s interference in the work diminished at her scholars advanced.'[12]

This negativity, again suggests the prejudice against a professional female artist, even when she was acting in the capacity as a teacher and copyist rather than as a portraitist.

Mary Black’s experiences as an artist stand as a fascinating example of the marginalisation of women in eighteenth-century London. The pastel of a Girl holding a Dog demonstrates the level of her technical skill, whilst its ambiguous subject-matter and exhibition at the Society of Artists in 1768 suggest Black’s awareness of contemporary strategies of display.  Preserved in remarkably good condition and in its original, carved gilt-wood swept frame the pastel is both an extremely beautiful decorative object and a potent reminder of the difficult position professional female artists occupied in the period.