The Crace family genealogy, written by his niece Elizabeth Smith, tells us that James 'met with his death by suffocation, whilst repairing a bath at his residence'.
My curiosity was piqued. How does one suffocate in a bath? The death certificate does not elucidate, and there are no surviving coroner's records for this part of Middlesex. But two newspaper reports of the inquest, accessed via The British Newspaper Archive, provide some background.
EXTRAORDINARY DEATH. -- Yesterday afternoon Dr. Lankester held an inquiry at the City of York, York-road, King's-cross, relative to the death of James Crace, 47 years of age. The deceased was the overseer of the bag department at the General Post Office, and on Monday morning last he rose at half-past six for the purpose of repairing a bath as an amateur. At a quarter to nine, as he did not appear at the breakfast table, search was made for him by his wife and daughter, when the former found him shut in the bath, with a brazier burning charcoal, the button of the lid having given way, and fastened him in. He was dead. The brazier was red hot. It being shown that there was no reason for his committing suicide by the French mode, a verdict of Accidental Death was recorded.
... the circumstances were, to say the least, suspicious. The deceased, James Crace, aged 47, had shut himself in a bath with a pan of charcoal, and had died from its fumes. The extenuating circumstance was, that the fastening of the door might have been unintentional, and that it could not be opened from the inside.
Nevertheless, the scenario is hard to envisage. A bath with a lid that fastens, with sufficient space for a man to shut himself inside (accidentally or not) and become asphyxiated by fumes from the charcoal brazier? I've not found any picture or description of a lidded Victorian bath that fits the bill. Any offers?