(Forgot to mention, this is in response to suggestions on the Discussion Prompt Thread.)
What did it mean for a woman or women to be 'queer' in late C19th Britain? Given that it was seen as natural and normal and even admirable for women in a largely homosocial world to have deep and romantically expressed devotions to other women and an appreciation of feminine charms?
The 'New Woman' - moving out of that world (sometimes on a bicycle, sometimes not). Seeking new transformed relationships with men. E.g. Olive Schreiner, the South African novelist, walking the streets of London at night having passionate arguments about philosophy and politics with her male friends, and nearly getting arrested as a prostitute on at least one occasion. Edith Lanchester, who did a science degree at University College London, was a member of the Marxist Social Democratic Federation (and at one point worked as Eleanor Marx's secretary), and decided to live in free union with a male comrade. Her middle class professional family, possibly as much appalled by the fact that he was a railway clerk as by the living in sin aspect, promptly had her certified as insane and taken to The Priory (whence, happy ending, she was soon released through prompt and effective action by her comrades). The vociferous campaigners against the double standard of sexual morality ('these women are worse than prostitutes'). The women who thought that they should be informed about the existence of and the dangers posed by sexually transmitted diseases. Women who were birth control advocates (hai, Annie Besant!) Etc etc. In context, in Dracula, Mina is perhaps queerer for being a self-supporting career woman with workplace skills than for having a devoted female friendship with Lucy.
However, there were women who had emotions towards other women and were involved in relationships that would, I think, be on the lesbian rather than the devoted friendship end of the spectrum. Specific individuals: Mary Benson (wife of Edward Benson, Archbishop of Canterbury); Amy Levy, poet and novelist; Vernon Lee, pseudonym of Violet Paget, writer on aesthetics and art history; 'Michael Field' (Katherine Harris Bradley) and her niece and ward Edith Emma Cooper), collaborative poet; the novelists Somerville and Ross, Edith Lees Ellis, novelist, writer and lecturer on social questions, wife of Havelock Ellis, friend of Edward Carpenter.
These were all fairly privileged women (except Edith Lees Ellis), and we have much less sense of non-middle class women and their relationships. However, Alison Oram's book Her Husband Was A Woman, although it is about cross-dressing women in the C20th, does include material that sheds light on the C19th, including some discussion of the very popular male impersonators of the music halls.
NB it wasn't illegal to be a lesbian in the UK (the first time sexual activity between women was featured in legislation was 1956), and it was not a matrimonial offence for the purposes of divorce. And there was absolutely no reason why anyone would have thought of including it in the Criminal Law Amendment Act of 1885, so it really wasn't omitted by Royal decree. Srsly. But this is one reason why it's so much less visible and studied than male homosexuality at the period - no legal records and no aghast newspaper reports. Which also relates to the fact that if it was happening, it was happening in private spaces rather than in public spaces where it was potentially visible to other people, or at least to the police.
Suggestions for reading:
Lilian Faderman's Surpassing the Love of Men: Romantic Friendship and Love between Women from the Renaissance to the Present (1981) remains a classic, even if subsequent scholars have nuanced her arguments.
Rebecca Jennings, A Lesbian History of Britain: Love and Sex Between Women Since 1500 (2007). This is very much a work of synthesis, and I found it a bit superficial, but it is actually a useful guide to the territory and the literature.
Martha Vicinus, Intimate Friends: Women Who Loved Women, 1778-1 928 (2004) deals largely with women who enjoyed privilege and resources (e.g. were able to live in the supportive community of women artists and writers in Rome!) but has some very interesting analysis of the ways in which these women conceptualised their relationships, drawing on letters, diaries, etc.
Sharon Marcus, Between Women: Friendship, Desire, and Marriage in Victorian England (2007). I found some of the chapters a bit problematic, but there is some remarkably acute and provocative stuff in this book, including the observation that Victorian novels, not to mention letters, diaries and memoirs, have women being romantically devoted right up front and without delving into the subtext.
I've already mention Oram's book on cross-dressers. There are also biographies of several of the women I've mentioned. Not yet seen, but sounds interesting: Jill R. Ehnenn, Women's Literary Collaboration, Queerness, and Late-Victorian Culture (2009) (wicked expensive)
Useful on New Women more generally: Martha Vicinus, Independent Women: Work and Community for Single Women (1985), 1850-1920 Judith Walkowitz, City of Dreadful Delight (1992), and Lucy Bland, Banishing the Beast: English feminism and sexual morality, 1880-1914 (1995). Unfortunately a lot of New Woman scholarship is heavily based on literary texts.
On new definitions of 'the lesbian' or 'female invert', the classic sexological texts are Krafft-Ebing's Psychopathia Sexualis, numerous and ever expanding editions from 1886, Havelock Ellis, Sexual Inversion (1897) and Edward Carpenter, Love's Coming of Age (1897) and The Intermediate Sex (1909). But all contain far more about male homosexuality. And because of the theory of 'inversion' with which they were working, can just about get their heads around butch-presenting lesbians (or at least those who demonstrate various markers associated with masculinity), but couldn't quite see, or analytically account for, more femme versions.