Rathmines was a popular suburb of Dublin, attracting the wealthy and powerful seeking refuge from the poor living conditions of the city from the middle of the 19th century. A substantial mansion, generally called Rathmines Old Castle, was built in the seventeenth century, probably at present-day Palmerstown Park, and rebuilt in the eighteenth; no trace of it survives today. Rathmines is arguably best known historically for a bloody battle that took place there in 1649, during the Cromwellian conquest of Ireland, leading to the death of perhaps up to 5,000 people. The Battle of Rathmines took place on 2 August 1649 and led to the routing of Royalist forces in Ireland shortly after this time. Some have compared the Battle of Rathmines – or sometimes Baggotrath – as equal in political importance to England's Battle of Naseby. The battle brought a swift end to the ongoing Royalist Siege of Dublin. In the early 1790s, the Grand Canal was constructed on the northern edge of Rathmines, connecting Rathmines with Portobello via the La Touch Bridge (which through popular usage became better known as Portobello Bridge). For several hundred years Rathmines was the location of a "spa" – in fact, a spring – the water of which was said to have health-giving properties. It attracted people with all manner of ailments to the area. In the 19th century, it was called the "Grattan Spa", as it was located on property once belonging to Henry Grattan, close to Portobello Bridge. The "spa" gradually fell into a state of neglect as the century progressed, until disputes arose between those who wished to preserve it and those (mainly developers) who wished to get rid of it altogether. In 1872 a Dr. O'Leary, who held a high estimate of the water quality, reported that the "spa" was in "a most disgraceful state of repair", upon which the developer and alderman Frederick Stokes sent samples to the medical inspector, Dr. Cameron, for analysis. Dr. Cameron, a great lover of authority, reported: "It was, in all probability, merely the drainings of some ancient disused sewer, not a chalybeate spring." Access to the site was blocked up and the once popular "spa" faded from public memory. Dublin Rathmines was a parliamentary county constituency at Westminster from 1918 to 1922. It returned Unionist candidate Maurice Dockrell as its MP in 1918, elected on a majority. Dockrell was the only Unionist