Emily Bronte wrote Wuthering Heights, one of the most iconic pieces of Gothic Friction ever, but with her death a year later the question has since been raised about a Second Novel that's existence might be questionable
What do we know?
Historical Fact
In 1848 Emily Bronte died (following her brother Branwell's death) and after the death of their sister Anne, Charlotte (the oldest sister) was in charge of their works which included Emily's masterpiece Wuthering Heights, Anne's novels Agnes Grey and The Tenant of Wildfell Hall and both sister's vast collections of Poetry. Charlotte republished Withering Heights and Agnes Grey with an Biography Notice which she tried to fan the controversial reception of Wuthering Heights by presenting her younger sisters as naive. There was no evidence that Emily tried writing another novel.
The Proof
Long after Charlotte's death and the opening of their home, the Parsonage as a Museum, many of their own belongings came back one of which was Emily's Writing Desk inside of which was two items that raised the questions of Emily's solo novel. The first is an Envelope addressed to Ellis Bell (Emily's writing name) it was opened and there was the second clue a letter addressed to 'Mr. Bell' it was written by Thomas Cutlery Newsy (Emily's publisher) saying he was willing to wait for the 'second' novel. However this is the only proof of a second novel.
Theories
It was Destroyed by the writer/sister
Since nothing else exists that proves Emily was writing another novel it is believed that either Charlotte or Emily destroyed the manuscript. The greater belief that Charlotte as she was clearing out anything that could harm her sisters posthumously, found the unfinished work and burnt it. Charlotte was in grief when she edited Emily's work to protect her so it's unsurprising that she would erase such a document from history. Emily might have done it herself, while ill of Tuberculosis she refused to seek medical attention trying to carry on but maybe when she realized that she was going to die she destroyed the work.
Emily's Bluff
This theory suggests that Newsy had been pressuring Emily to write a second novel, so in anger, the private Emily Bronte sent him a lost letter claiming she was writing another novel to get him off her back deciding not to write one at all or agreeing to write one after an earlier request letter but requesting time.
It's Not Emily's Letter
While the Envelope exists written to Ellis Bell, could the Letter be one given to Acton Bell who is Anne Bronte? The reason is that the letter dates from February 1848 and in June 1848 Anne's second novel, The Tenant of Wildfell Hall. Since the only belief that it was for Emily was because it was found in her desk but at the same time Anne's Desk was empty. Also, the letter's writer Newsy might have been talking to Emily hoping she claimed to be writing forgetting that Anne is the one sending him news about T.T.O.W.H. After the novel's success, he claimed to the US Publisher that all works by the Bells were written by the same person Ellis, which also included Charlotte's Novel Jane Eyre, which resulted in Charlotte and Anne going to London to Charlotte's publisher proving that there was 3 different writers.
Legacy
While it's clear that if the manuscript existed, it is now probably gone forever, the theories that explain the truth will keep going and especially the content of such a Novel, has many claiming that a Sequel for Wuthering Heights was the plan, however, Emily's imagination was one of mystery and originality that it might of been something very different.