I ran across this great history of the O'Shaugnessy fish hook in Limerick; Its History and Antiquities by Maurice Lenihan (Dublin, 1866). He notes that the once great reputation of Limerick hooks had all but died by the 1860s, with only one master hook maker left. It's a fabulous history and I've not seen this information repeated elsewhere.
The proverbial celebrity which the fishing hooks of Limerick have won, is nearly gone--every fishing hook was said to be worth a salmon; their form, lightness, and temper could not be imitated.
The Limerick fishing hooks were celebrated all over the world. Daniel O'Shaughnessy, about sixty years ago, was one of the most famous—if not the most famous fishing hook maker in his day. He was succeeded by his son John, who died without issue; and though the "Shaughnessy" hooks have been sold until very recently, there has been no person of the name in the manufacture of them since the death of Mr. Robert O'Shaughnessy of George's Street, who employed hook-makers, and who continued to sell the "Shaughnessy" hooks. William Selles, or Lascelles, succeeded the second of the O'Shaughnessys in the manufacture, and was an adept. Michael Selles of Quay Lane, his son, succeeded William, and is now (1866) living, and is the last of the manufacturers of these celebrated articles; he is poor though industrious.
The material of which these hooks are made is cast-steel, which is given out to nailers in the country, who heat the steel in a turf fire to a certain peculiar temperature, taking great care that it must not be over-heated. It is then beaten out by the nailer, and in that condition it is brought to the hook-maker. Sellers of Croom was justly prized for his success in preparing the cast steel. The hook-maker then did his part. He formed the hook out of the solid, gave it the symmetrical form while the steel continued soft, and then tempered it, producing an article unrivalled. English manufacture of a bad imitation has nearly extinguished the make; but whilst Michael Selles of Quay Lane lives, the disciple of Isaac Walton can obtain a first-class salmon hook for 2d. and a trout hook for a lesser sum.
-- Dr. Todd