For those areas and classes they cover, Irish directories are an excellent source, often supplying information not readily available elsewhere. Their most obvious and practical use is that of finding out where precisely in the larger towns a family lived; but for members of the gentry and for the professional, merchant and trading classes they can show much more, providing circumstantial evidence of reversals of fortune or growing prosperity, of death or emigration. In many cases, directory entries are the only precise indication of occupation. The only classes totally excluded from all directories are, once again, the most disadvantaged: small tenant-farmers, landless labourers and servants. Virtually all classes other than these are at least partly included, in some of the nineteenth-century directories in particular. One point to be kept in mind when using any directory is that every entry is at least six months out of date by the time of publication.
The Gentleman's and Citizen's Almanack produced by John Watson, began publication in Dublin in 1736 and continued until 1844. However, the first true trade directories in Ireland were those published by Peter Wilson for the city of Dublin, beginning in 1751 and continuing until 1837, with a break from 1754 to 1759. From the outset these were considered as supplements to Watson's Almanack and were regularly bound with it. In 1787 the two publications were put together with the English Court Registry, and, until it ceased publication in 1837, the whole was known as The Treble Almanack.
Initially the information supplied in Wilson's Directory consisted purely of alphabetical lists of merchants and traders, supplying name, address and occupation. In the early years these were quite scanty, but they grew steadily over the decades, from less than a thousand names in the 1752 edition to almost five thousand in 1816. The last decades of the eighteenth century also saw the inclusion of separate lists of those who might now be termed the 'establishment': officers of the city guilds and of Trinity College, state officials, those involved in the administration of medicine and the law, Church of Ireland clergy etc. The range of people covered expanded markedly, if a little eccentrically, in the early nineteenth century. The most permanent addition was a new section, added in 1815, that covered the nobility and gentry. A number of other listings of potential use to readers were also added, though some appear only intermittently. Persons covered by these lists include pawnbrokers, bankers, apothecaries, police, dentists, physicians, militia officers and ships' captains.
The most significant difference between the Treble Almanack and Pettigrew and Oulton's Dublin Almanac and General Register of Ireland, which began annual publication in 1834, is the inclusion in the latter of a street-by-street listing, initially only of the inhabitants of Dublin proper but enlarged annually to encompass the suburbs. From 1835 this listing was supplemented by an alphabetical list of the individuals recorded. In theory at least, the combination of the two listings should now make it possible to track the movements of individuals around the city-an important feature, as changes of address were very frequent in the nineteenth century, when the common practice was to rent rather than purchase. Unfortunately, in practice the alphabetical list is much less comprehensive than the street list.
Pettigrew and Oulton also extended even further the range of persons covered. The officers of virtually every Dublin institution, club and society are recorded, as are clergy of all denominations. Another significant difference from the earlier Treble Almanack that should be kept in mind is the extension of the coverage outside the Dublin area. Under the rubric 'Official Authorities of Counties and Towns', Pettigrew and Oulton recorded the names of many of the rural gentry and of more prosperous inhabitants of the large towns, in their guise as local administrators. This is particularly useful for areas that were not served by a local directory or for which none has survived. Similarly, the officials of many of the better-known institutions and societies in the larger country towns are also recorded, together with the more important provincial clergy.
An important competitor to Pettigrew and Oulton was the Post Office Annual Directory and Calendar published by John S. Folds between c.1832 and c.1858. Although it does not include a street directory, almost three hundred pages give alphabetical listings of the nobility, gentry, merchants and traders of Dublin-a very comprehensive record of the pre-Famine city. There are also separate directories for the professions, including attorneys, barristers, benchers of the King's Inns, medical practitioners, surgeons and apothecaries. The Annual Directory was eventually put out of business by Thom's.
Alexander Thom's Irish Almanac and Official Directory, which began in 1844 and has continued publication up to the present, is by far the best-known Irish directory. As the name implies, it continued Pettigrew and Oulton's extension of coverage outside Dublin. To take one year as an example, the 1870 edition includes, as well as the alphabetical and street listings for Dublin, alphabetical lists of the following for the entire country: army officers; attorneys, solicitors and barristers; bankers; Catholic, Church of Ireland and Presbyterian clergy; coastguard officers; doctors; members of Parliament; magistrates; members of the Irish Privy Council; naval and marine officers; officers of counties and towns; and peers. Although Thom's is generally regarded as a Dublin directory, its usefulness goes well beyond Dublin.
Dublin was also included in the countrywide publications of Pigot and Slater, issued at intervals during the nineteenth century. The only significant difference is the arrangement of the individuals listed under their trades, making it possible to identify all those engaged in the same occupation-important at a time when many occupations were handed down from one generation to the next. These directories are dealt with more fully in the 'Countrywide' section.
Askaboutireland.ie has free browsable and full-text searchable access to Thom's 1862, 1887-89, 1892, 1912, 1921 and 1925-1988, with some gaps in the later run. Entrance, strangely, is via the Askaboutireland Griffith's Valuation home page.
Archive CD Books Ireland (www.archivecdbooks.ie) began the process of re-publishing early directories on CD-ROM in early 2005, and have now (August 2018) republished: six editions of The Treble Almanack (1783, 1812, 1814, 1818, 1822 and 1829); two editions of Pettigrew and Oulton(1835 and 1842); Fold's Post Office Annual Directory and Calendar (1843 and 1858) and four editions of Thom's, between 1868 and 1910. All of these are also available via FindMyPast]. FindMyPast also has an index of personal names linked to page images from Thom's 1844-1900 and the Treble Almanack 1835-1845. These do not permit page-by-page browsing or searches on street names and occupations, so limiting their usefulness.
Ancestry.com's collection ' Ireland, City and Regional Directories, 1836-1947' (dbid 61314) includes an almost complete run of Thom's from 1847 to 1904 and a fully complete run from 1906 to 1946, searchable by personal name, occupation and 'Keyword', which can be an element from the address, as well as Pettigrew and Oulton from 1836 and 1838.
Pettigrew and Oulton (1842) is available free at www.failteromhat.com. The Treble Almanack from 1804 and 1832 is on books.google.com, along with Pettigrew and Oulton from 1847 and Thom's from 1850, 1851, 1852 and 1876. Shane Wilson's site, swilson.info, has full text and image sets of Watson's for 1783, Wilson's for 1804 and Pettigrew and Oulton for 1834 and 1840. Shane also has an excellent regularly-updated guide to what directories are online.
The LDS Family History Library has a good though not complete run of Thom's on microfilm. A few of the films are publicly viewable on FamilySearch.org - search the catalogue for Ireland - Directories and look out for the camera icon beside the film reference. It does not appear to have any of the pre-Thom's Dublin directories.