In the heart of the Luxembourg’s Sauer Valley, acclaimed for its picturesque landscapes, you can find the village of Rosport. You might have come across that name when ordering mineral water in one of Luxembourg’s restaurants, but Rosport is well known beyond its springs. Indeed, the Musée Tudor in Rosport is dedicated to the town’s most famous son, Henri Owen Tudor (1859 – 1928), an engineer of British descent who invented the first practical lead- acid accumulator. It all began with John Thomas Tudor, the Welsh-born father of Henri Owen Tudor. He moved to Belgium, France and Luxembourg and ended up being hired at the Loser family’s estate, the Irminenhof in Rosport, as an agricultural engineer in 1839.