In 1877 we have G. McIlhagga, clerk, living at 66 Eglinton Street; John McIlhagga, clerk, at 99 Charles Street South; Samuel McIlhagga, flax-buyer, at 33 North Queen Street and Nathaniel O. McIlhagga (of McIlhagga & Co.) at Antrim Road. In 1880 we learn the name of Nathaniel's house. It is 'Loughview', and in addition we have Samuel McIlhagga, car owner, at 27 Abbey Street and W. McIlhago, another mill furnisher at 38 Lavinia Street. By 1890 we can add James McIlhagga, a flax dresser, at 36 Disraeli Street, Eliza McIlhagga at 53 Berlin Street and John McIlhagga, a Labourer, at 92 Island Street. McIlhagga & Co., furnishers, have moved to 84-88 Great Patrick Street. Nathaniel now calls his house 'Lough View Cottage'. In 1892 a Mrs. McIlhaggan appears at an undecipherable address.
Moving into the first decade of the 20th Century we have two bakers, J. McIlhagga at 45 Wigton Street and William McIlhagga at 18 St. Mary's Street. In the same line of work there is Robert McIlhagga, confectioner at 294 Crumlin Road and John McIlhaggo, a bread server at 26 Sheridan Street. W.J. McIlhagga, a foreman, lived at 299 Albert Bridge Road and N. McIlhagga has moved to 'Merryfield' in Cavehill Road.
By 1907 the variety of occupations has increased a little. David McIlhagga, shipwright was at 35 Parkmount Street, D. McIlhagga, coal merchant, at 66 Agnes Street, John McIlhagga, car owner, at 164 New Lodge Road, John McIlhagga, baker at 41 Cumberland Street, Mary McIlhagga, confectioner, 59a Newtonards Road, Wm. J. McIlhagga, fruiterer, 204 Ormeau Road, William McIlhagga, ship carpenter, 13 Eccles Street, R. McIlhaggart, baker, 30 Lowther Street and George McIlhagger an ex-sergeant in the Royal Irish Constabulary had retired to live at 29 New North Queen Street. N.O. McIlhagga must have died as 'Loughview Cottage' in Cavehill Road was now occupied by Mrs. N. McIlhagga.
Three years later in 1910 some of the 1907 names and addresses are repeated: John (car owner), John (baker), Mary, Mrs. N, William, Wm.J., and George. In addition there were David McIlhagga, confectioner at 90 York Road, and James McIlhagga oil merchant at 18 Madison Avenue. The only later Directory that I have been able to check is the 1913 Telephone Directory. No individuals are listed but 'McIlhagga & Co.' has an early telephone number - Belfast 744.