I’ve been finding a number of conflicting accounts as to the inventer of the rubber eraser. A number of books I have read attribute either a Portuguese physicist named Magalhaens or Magellan, who apparently invented it in 1725 or 1726 according to some sources or the 1860’s, according or others, or an English scientist named Joseph Priestley in 1770. However, the BayerRubber website (https://www.rubber.bayer.com) has a timeline of rubber history that attributes its creation to an Englishman called Edward Nairne, also in 1770.
Raw rubber as erasers, “peaux de negres” would have been in Europe since the discovery by European exploers of South America, but the modern eraser would have arisen between c.1839 (Charles Goodyear vulcanizing rubber for durability) and 1858 when Hyman Lipman applied an eraser to the end of a pencil. A bit more info here.
My Mirriam-Webster cites the term from 1790. While that lends some credibility to something like the Priestly attribution, I’d love to see Priestly’s actual words.
I found one internet PDF file that claims that Priestley’s description of the properties of rubber preceded the material’s use in France. It also attributes Eduard (it is spelt “Edward” at Bayer Rubber) Nairne with coining the term, “rubber”, for the eraser.
It is apparently the, “Newsletter Of The Rubber Foundation Information Center For Natural Rubber.”
“It was in 1770, in Priestley’s “Familiar Introduction to the Theory and Practice of Perspective”, that a use for caoutchouc was first reported. In the preface he wrote, “Since this work was completed, I have seen a substance that is perfectly suited to erase pencil lines by rubbing.” Eduard Nairne, a London instrument maker, sells pieces of about half an inch of this product for three shillings. The characteristic discovered by Nairne (1726-1806) gave the product the name “rubber”. In 1775, small rubber cubes were sold in France under the name “Peaux de Nègres.””
There do not appear to be any English websites that mention Magalhaens, although this French one reports him, rather cryptically, as the eraser’s inventer. It says however, that the first verified (proven) account of the eraser’s properites was Priestley’s.
Here’s a cite from the OED which is probably what my M-W was referring to: under “rubber” they cite
1788-9 HOWARD New Royal Encycl., s.v. Caoutchouc, Very useful for erasing the strokes of black lead pencils, and is popularly called rubber, and lead-eater