1781 "December 22 James Olivant Son of James & Sophia Delahoy" was baptized at St Ann Blackfriars, London. 
1808 "James Olivant Delahoy, bachelor" of St Alfege, Greenwich, and "Elizabeth Omer, spinster of the Parish of St Paul, Deptford, Kent, were married" in St. Alphege Church in Greenwich, England, on the nineteenth of May, "in the presence of John Omer (Elizabeth's father), Mary Omer and Charlotte Omer (Elizabeth's sisters), and Sophia Delahoy (James' mother, or possibly his sister)." 
1808 "A List of the Master Printers" named Delahoy, Deptford-bridge .
1808 On August 19, just three month after their marriage, James and Elizabeth suffered a disasterous fire. “A fire broke out about two o’clock on Friday morning, at the house of Mr. Delahoy, jun., stationer, in Limekiln-road, Deptford, leading to Blackheath. The house was entirely consumed, and the maid-servant lost her life.” 
1809 On August 25, daughter Elizabeth was born at No. 6 Deptford Bridge, in the Parish of St. Alphege, Greenwich, Kent. In attendance were J.L. Shirreff, surgeon, and Sophia Delahoy. 
1811 On January 26, daughter Sophia Olivant was born in S Alphage Greenwich, Kent, England. 
1812 On March 5, James Olivant Delahoy died. He was buried on March 13 at St. Paul's Church, Deptford . Edith Miles Todd wrote, “James Delahoy died of consumption brought on by exposure shock after fire in his printing house, 2nd fire in 2 or 3 years and he was suspected for a time. My granddmother writes of this fire and says he almost lost his life in it and very valuable manuscripts (family) were destroyed in it.”
1812 On May 14, James Delahoy’s will was proved in London , leaving all his possessions including his printing equipment to his wife Elizabeth.
In the name of God Amen, I James Olivant Delahoy Printer and Stationer of Deptford bridge in the Parish of Greenwich Kent being sound in mind though infirm in body do make this my last will and testament in manor & form following first after my just debts are paid I give and bequeath to my lawful wife Elizabeth Delahoy daughter of John Omer Bookseller of Chatham Kent all the Printing Materials in my office on Blackheath Road together with my book debts Goods and Chattels with whatever property I may be found possessed of with full rest and residue for her own use thus leaving her my only and sole heiress with full right and title thereto And I do hereby appoint the said Mr. John Omer Bookseller of Chatham Kent and and Mr. Thomas Pewtress Stationer of Newington Causeway in the County of Surry my Executors and I desire that Mr. Omer and Mr. Piwtress may each have a ring.
24th April 1812 On which day appeared personally James Hackett of No. 58 Newington Causeway in the County of Surry Paperhanger and Charles Oram of No. 62 Newington Causeway aforesaid Gentleman and being severally sworn on the holy Evangelists to depose the truth respectively made oath as follows (that is to say) that they knew and were well acquainted with James Olivant Delahoy late of the parish of Greenwich in the County of Kent for some time before and to the time of his death and that by means of having frequently seen him write and also write and subscribe his name they are become well acquainted with his manner and character of handwriting and subscription and that having now with particular care and attention viewed and perused the paper writing hereunto annexed purporting to be and contain the last will and testament of the said deceased beginning thus “In the Name of God Amen I James Olivant Delahoy printer and Stationer of Deptford bridge in the parish of Greenwich Kent” ending thus “and I desire that Mr. Omer and Mr. Piwtress may each have a ring” They say that they do verily and in their consciences believe the whole views and contents to the said will and the said writed Names “James Olivant Delahoy” so appearing written at the beginning of the said Will to be all of the proper handwriting and subscription of the said James Olivant Delahoy deceased. Jas Hackett Chas. Oram. Same day the said James Hackett and Charles Oram were duly sworn to the truth of this affidavit before me S. Paroon Sur P. Bu. Wills Not Pub.
Proved at London 14th May 1812 before the Whpful Samuel Pearce Paroon Dr of Laws & Surr by the oaths of John Omer & Thomas Pewtress the Exors to whom admon was granted being first sworn duly to admr.
1812 On 19 September, daughter Charlotte was born in S Alphage Greenwich, Kent, England. 
1820 "Eliz. Delahoy, Albion Printing Office, 3, Deptford Bridge, Greenwich" printed A Selection of Hymns from the Best Authors by John Rippon. 
1823 On 30 October, Elizabeth Delahoy and Mark Moore were married at Saint James Church, Westminster, Middlesex, England Marriage. 
1824 "An aplhabetical list of printers" listed "Delahoy, Mrs. Deptford-bridge" .
1841 Mark Moore (age 61), private boarding house keeper, Elizabeth Moore (age 55) and Charlotte Delahoy (age 28) lived 6 Queen Street Place, District 15, St Martin Vintry, Middlesex. 
1851 Elizabeth Moore (age 64), boarding housekeeper, lived at 5 Queen Street Place, District 16, St Martin Vintry, Middlesex with Lydia Moore (age 24), daughter Charlotte Jennings (age 36), and son-in-law Angus Jennings (age 34), merchant. Elizabeth was born in Deptford, Kent. Lydia and Charlotte were born in Greenwich, Kent, and Angus was born in Herts. 
Edith Miles Todd wrote in her genealogy notes that the Delahoy family was of Huguenot origin. 
The Delahoys (De La Hayes) of Huguenot origin. The family notable in France and when they first emmigrated to England, but lost all of their possessions. Gilbert Jennings says a lot went to worthless relatives named Merrick. [James Olivant Delahoy's sister married a Merrick.] ... [James] was cast off by family for being a Calvinist and Baptist. Was of a splendid character however. Signs himself Jr. in 1808 in a letter to his sister-in-law Charlotte Omer (which I possess). His wife married again Mark Moore and had 2 children Mary (d.y.) and Lydia (Burr). I have seen his will which Gilbert Jennings owns and have a copy of it. In my grandmother's Bible which I have is a copy of births and deaths from the Bible of Elizabeth Omer Delahoy Moore. She says that James O. was 29 years 4 months when he died. Also says died Mar. 5, 1812.
The Exeter Working Papers in British Book Trade History [http://www.devon.gov.uk/library/locstudy/bookhist/] provides the following information about James Delahoy but has merged information for the James and his son James Olivant as it is the printing operation of James Olivant Delahoy that was bequeathed to and continued by his wife Elizabeth. The senior James became an auctioneer after his career as a printer.
The London book trades 1775-1800: a preliminary checklist of members [http://www.devon.gov.uk/library/locstudy/bookhist/lonbktr.html],
Delahoy, James, printer, auctioneer and broker Deptford Bridge 1795-1809H. Ran Kent Printing Office 1795. Succ. by Mrs. Elizabeth Delahoy 1808-24. Also described as copperplate printer, stationer and binder of 96, Deptford Bridge 1817U.
The London book trades 1775-1800: a topographical guide [http://www.devon.gov.uk/library/locstudy/bookhist/street.html],
Deptford Bridge. Deptford
1808 -1824 Delahoy, Elizabeth PR
1817U Delahoy, Elizabeth PR
1795 -1809H Delahoy, James PR
See also Todd, William Burton. A directory of printers and others in allied trades, London and vicinity, 1800-1840. London: Printing Historical Society, 1972.
 London Metropolitan Archives, St Ann Blackfriars, Register of baptisms, 1701 - 1812, P69/ANN/A/001/MS04508, Item 002, London, England, Baptisms, Marriages and Burials, 1538-1812, City of London, St Ann Blackfriars, 1701-1812, image 318, [Ancestry_Image].
 London Metropolitan Archives, Saint Alfege, Greenwich, Register of marriages, P78/ALF, Item 035, London, England, Marriages and Banns, 1754-1921, image 5, [Ancestry_Image].
 C. Stower, The compositor's and Pressman's Guide to the Art of Printing (London: 1818), 128, [HathiTrust].
 Newspaper, The Bury and Norwich Post, Or, Suffolk, Norfolk, Essex, and Cambridge Advertiser (Bury Saint Edmunds, England), Wednesday, August 24, 1808; Issue 1365. 19th Century British Library Newspapers: Part II.
 FamilySearch.org, [FamilySearch_Record].
 FamilySearch.org, citing FHL film 815986, [FamilySearch_Record].
 FamilySearch.org, citing FHL film 596982, [FamilySearch_Record].
 FamilySearch.org, England and Wales, Non-Conformist Record Indexes (RG4-8), [FamilySearch_Record].
 FamilySearch.org, citing FHL film 254584 of Bishops transcripts for St. Paul's Church, Deptford, [FamilySearch_Record].
 The National Archives of the United Kingdom Catalog, Will Registers, Oxford Quire Numbers 206 - 258, Prob 11/1533/227, [UK_National_Archives].
 FamilySearch.org, citing FHL film 596982, [FamilySearch_Record].
 John Rippon, A Selection of Hymns, from the best authors (London: Eliz. Delahoy), [Google_Book].
 FamilySearch.org, citing FHL Film 1042319, Parish registers, Church of England, St. James' Church (Westminster), Microfilm of original records in the Westminster City Library, Victoria Library no.: 494/14-47, [FamilySearch_Record].
 J. Johnson, Typographia or the Printer's Instructor, Vol. 2 (London: 1824}, [Google_Book].
 England Census, 1841, [Ancestry_Image].
 England Census, 1851, [Ancestry_Image].
 Edith Billing Miles Todd, "Ancestors of Edith Marian Billing Miles," Manuscript, FHL Fiche 6004403, [FHL_Catalog].