Caption: Lord Rosse (1800-1867): i.e., William Parsons, Lord Rosse, formally 3rd Earl of Rosse (1800-1867), AKA Himself (Wikipedia: Hiberno-English: Reflection for emphasis: Himself).

Lord Rosse was an Irish astronomer (and Irish peer and landowner) famous for the contructing the Leviathan of Parsonstown (reflector, primary diameter 1.83 m = 6 ft, operational 1845--c.1890) the record largest telescope (i.e., the telescope with the largest primary) until 1917 when it was superpassed by the 2.54-meter (100-inch) Hooker telescope at Mount Wilson Observatory in California (see Wikipedia: Timeline of telescopes, observatories, and observing technology: 1800s).

With the Leviathan, Lord Rosse discovered the spiral nature of the spiral nebulae which we now call spiral galaxies.

By the by, one wonders what Himself (Wikipedia: Hiberno-English: Reflection for emphasis: Himself) thought of his indirect ancestor Richard Parsons, 1st Earl of Rosse (1702--1741) (earl of the first creation of the Earldom of Rosse). This ancestral Earl of Rosse was a notorious libertine and rake---yours truly can see a bit of hellfire in the eyes of Himself.

By the by also, Lord Rosse had a famous son: Sir Charles Parsons (1854--1931), inventor of the modern steam turbine in 1884.

Credit/Permission: Anonymous photographer, 19th century before or circa 1867 (uploaded to Wikimedia Commons by User:Billinghurst, 2008) / Public domain.
Image link: Wikimedia Commons: File:William Parsons, 3rd Earl of Rosse photo.jpg.
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