Here’s a high resolution version of the Powerscourt family portrait, taken in 1901. Lord Powerscourt, 7th Viscount, is seated in the centre, with his wife behind him and children behind him, including the future 8th Viscount, who had just come of age. The 7th Viscount died in 1904. There are several Enniskerry notables are in the picture, including Lord Monck of Charleville. Thanks to Úna Wogan for this high resolution version.
The Irish Times republished the photograph several years later, giving a list of those in it.