Kelly Grovier in BBC:
In 1805, a little-known English artist and amateur painting instructor did what no woman before her ever had: publish a book on the subject of colour theory. Though frustratingly few details of the life and career of Mary Gartside have survived, her unprecedented volume An Essay on Light and Shade, on Colours, and on Composition in General reveals evidence of extraordinary creative genius. Modestly introduced by its obscure author as little more than a guidebook to “the ladies I have been called upon to instruct in painting”, Gartside’s study is accompanied by a series of strikingly abstract images unlike any produced previously by a writer or artist of any gender.
At first glance, you could easily mistake Gartside’s eight watercolour “blots” for magnified floralscapes that anticipate the outsized stamens and pistils that the US artist Georgia O’Keeffe would begin exploding out of all proportion more than 100 years later. But look again at these lucent surges of almost petals, whose vibrancy of colour is unshackled to tangible shape, and any certainty you may have had about what it is that these images portray or what they mean begins to break down. Neither fragrant blossoms plucked from the real world nor imaginary blooms unfolding in the mind, Gartside’s abstract blots burst beyond the borders of themselves a full century before non-figurative painting established itself on the better-known canvases of Wassily Kandinsky, Kazimir Malevich and Piet Mondrian.