In the 19th century, women writers often used male pen names to avoid prejudice and be taken seriously by publishers and readers. The Brontë sisters each adopted masculine-sounding pseudonyms:
Charlotte Brontë became Currer Bell
Emily Brontë became Ellis Bell
Anne Brontë became Acton Bell
They all kept the same initials as their real names.
So when Wuthering Heights was first published in 1847, it was under the name Ellis Bell, not Emily Brontë.