Sorry that I can't shed any light on the cause of death or circumstances surrounding it, but I have found some info about Thomas Marshall...

Birth: 28 August 1820 in Linton Hill, Herefordshire

Christening: 15 October 1820 in Linton Hill

Marriage (to Sarah Goode): 07 May 1843 in Walford, Ross, Herefordshire

Was living in Linton Hill in 1851 according to 1851 census

Death: 10 July 1854 in Linton Hill

His parents were Richard Marshall (1785-1871) and Margaret Clay (1774-1866)

Hopefully this is of some use. Good luck finding out about the death itself.
Chris