Two sculptures beside the beautiful canal bridge at Broombridge, in memory of the day in 1843 that 38-year-old William Rowan Hamilton, walking with his wife Helen, scratched the recipe for quaternions into the stone of the bridge in case he'd forget it later
#Quaternions #RowanHamilton #Broombridge
Here's his grandson, John O'Regan (son of the daughter of Hamilton; she died after John's birth in 1870) getting married in 1912. Looks like the family were lost to Ireland after that
https://www.irishgenealogy.ie/files/civil/marriage_returns/marriages_1912/09913/5602747.pdf

@sinabhfuil John O'Regan's wife Phoebe Abbott in the 1911 census https://nationalarchives.ie/collections/search-the-census/census-record/#surname__icontains=Abbot&firstname__icontains=Phoebe&limit=30&id=2976805&c20_year=1911

John himself appears to have died in 1922 but not before fathering six children.

He also appears to have written a book https://openlibrary.org/books/OL7224876M/The_German_war_of_1914

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