She was a great friend of May Morris, Wikipedia says they lived together in Majorca for a while (Leicester gallery says it was a holiday) and a frequent visitor to Kelmscott where she painted May several times. She also seems to have been very interested in the woman's movement as well as being a gifted artist.
Most of this exhibition is made up of watercolours and etchings, a lot of them from private collections, which I think might mean family and friends, and there are slide shows of more of her work not on display (not lent?).
Leicester's New Walk gallery has some interesting things - it has probably the best collection of German Exspressionism to be found outside of Germany, a lot of Picasso ceramics, and some lovely arts and crafts peices, mostly related to Earnest Gimson. These all fight for space with a motley collection of stuffed animals, some mummies and other Egyptian bits, some dinosaurs (all beloved of young children across the county) and other assorted exhibits. In short there's not enough space to do any of it real justice.
The result for Mary Annie Sloane (who I don't think is getting enough publicity) is that quite a large body of work is crammed into two small rooms with a minimum of interpretation, and whilst I'm grateful that this exhibition is happening at all, she deserves more. Even just from a local perspective her sketches of prominent women, and her own roll in the women's movement and social reform would be worth looking at more closely. Her friendship with May Morris also deserves more space, how much did they influence or inspire each other - I'd like to know! And generally just more space to look at everything would be good.
On a less negative note the exhibition is free and on until early July. There is a very short guide which I'll buy next time I go - I want to see this a few times to let it sink in - and at least we're getting to see a decent body of her work, certainly enough to get a proper sense of Mary as an artist. It's not a perfect exhibition, but it's well worth making the effort to see.