Joseph Carey Merrick (5 August 1862 - 11 April 1890), often incorrectly called John Merrick, was an English man with very severe face and body deformities who was first exhibited at a freak show as the "Elephant Man", and then went to live at the London Hospital after he met Frederick Treves, subsequently becoming well known in London society. Merrick was born in Leicester, and began to develop abnormally during the first few years of his life: his skin appeared thick and lumpy, he developed enlarged lips, a bony lump grew on his forehead, one of his arms and both of his feet became enlarged and at some point during his childhood he fell and damaged his hip, resulting in permanent lameness. When he was 9, his mother died from bronchopneumonia, and his father soon remarried. Merrick left school at the age of 13 and had difficulty finding employment.

On three occasions Merrick left the hospital and London on holiday, spending a few weeks at a time in the countryside. Through elaborate arrangements that allowed Merrick to board a train unseen and have an entire carriage to himself, he travelled to Northamptonshire to stay at Fawsley Hall, the estate of Lady Knightley. He stayed at the gamekeeper's cottage and spent the days walking in the estate's woods, collecting wild flowers. He befriended a young farm labourer who later recalled Merrick as an interesting and well-educated man. Treves called this "the one supreme holiday of [Merrick's] life", although in fact there were three such trips.  Merrick's condition gradually deteriorated during his four years at the London Hospital. He required a great deal of care from the nursing staff and spent much of his time in bed, or sitting in his quarters, with diminishing energy. His facial deformities continued to grow and his head became even more enlarged. He died on 11 April 1890, at the age of 27. At around 3:00 p.m., Treves's house surgeon visited Merrick and found him lying dead across his bed. His body was formally identified by his uncle, Charles Merrick. An inquest was held on 15 April by Wynne Edwin Baxter, who had come to notoriety conducting inquests for the Whitechapel murders of 1888.  Merrick's death was ruled accidental and the certified cause of death was asphyxia, caused by the weight of his head as he lay down. Treves, who performed an autopsy on the body, said that Merrick had died of a dislocated neck. Knowing that Merrick had always slept sitting upright out of necessity, Treves came to the conclusion that Merrick must have "made the experiment", attempting to sleep lying down "like other people".  Treves dissected Merrick's body and took plaster casts of his head and limbs. He took skin samples, which were later lost during the Second World War, and mounted his skeleton, which remains in the pathology collection at the Royal London Hospital. Although the skeleton has never been on public display, there is a small museum dedicated to his life, housing some of his personal effects.Answer this question using a quote from the following article:

What was the cause of death?
Merrick's death was ruled accidental and the certified cause of death was asphyxia, caused by the weight of his head as he lay down.