Maryborough in Portlaoise in County Laois, Leinster, Ireland — Mid-East (and Dublin)

Portleix House

— Portlaoise Heritage Trail / Slí Oidhreachta Port Laoise —

Photographed by Ian Lefkowitz, May 17, 2026

1. Portleix House Marker

Inscription. This was for many years the home of the famous Jacob medical family. An early Dr. Jacob founded the first infirmary in Maryborough (now Portlaoise) in 1756. His son, Dr. John Jacob, founded the County Infirmary in 1808 and built this house c.1810. John’s son, Dr. Arthur Jacob, discovered the membrane of the eye, afterwards called “Membrane Jacobi”.

In 1912 this became the Parochial House and was renamed “St. Josephs”. Three beloved Portlaoise P.P.s lived here: Dr. Michael J. Murphy (P.P. 1901–’41), Very Rev. Thomas Browne (P.P. 1941–’76) and Very Rev. Gregory Brophy (P.P. 1976–’92).

Erected by Laois Heritage Society.

Topics. This historical marker is listed in these topic lists: Religion & Religious Structures • Science & Medicine. A significant historical year for this entry is 1756.

Location. 53° 2.111′ N, 7° 17.626′ W. Marker is in Portlaoise, Leinster, in County Laois. It is in Maryborough. It is on Dublin Road. Touch for map. Marker is at or near this postal address: 4 Dublin Road, Portlaoise, Leinster R32 KX9H, Ireland. Touch for directions.

Regionally, it is on the Atlantic Ocean,

in the North Atlantic

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Region,

in Europe,

on the Island of Ireland,

on the Celtic Fringe,

in the European Union,

in Atlantic Europe,

on one of the British Isles,

in the Western World,

and in the Anglosphere.

Other nearby markers. At least 8 other markers are within walking distance of this marker: Burial Ridge of Maryborough (within shouting distance of this marker); Bartholomew Mosse (about 180 meters away, measured in a direct line); Presentation Convent (about 210 meters away); World War I Centennial Plaque (about 210 meters away); 4th Battalion Leinster Regiment Memorial (about 210 meters away); SS Peter and Paul Church (about 210 meters away); Irish Veterans Memorial (about 210 meters away); Dún Phort Laoise / The Fort of Portlaoise (about 210 meters away). Touch for a list and map of all markers in Portlaoise.

Also see . . . Arthur Jacob (Wikipedia).

Arthur Jacob (1790–1874) was an Irish ophthalmologist. He is known for founding several hospitals, a medical school, and a medical journal. He contributed to science and academia through his 41-year term as Professor of Anatomy at the Royal College of Surgeons in Ireland (RCSI) and
Photographed by Ian Lefkowitz, May 17, 2026

2. Portleix House Marker
The marker is located near the entrance to the Portleix House.
as the first Irish ocular pathologist...In 1819 Jacob announced the discovery, which he had made in 1816, of a previously unknown membrane of the eye, in a paper in the Philosophical Transactions. The membrane has been known since as membrana Jacobi and forms the retina.

(Submitted on July 11, 2026, by Ian Lefkowitz of New York, New York.)

Credits. This page was last revised on July 15, 2026. It was originally submitted on July 11, 2026, by Ian Lefkowitz of New York, New York. This page has been viewed 12 times since then. Photos: 1, 2. submitted on July 11, 2026, by Ian Lefkowitz of New York, New York. • Andrew Ruppenstein was the editor who published this page.