 Soon, lines up the Merrimack to Nashua, downriver to Lawrence, and inland to Groton Junction, today known as Ayer (renamed after Lowell patent medicine tycoon Dr. James Cook Ayer), were constructed.Uriah A. Boyden installed his first turbine in the Appleton Mill in 1844, which was a major efficiency improvement over the old-fashioned waterwheel.The turbine was improved at Lowell again shortly thereafter by Englishman James B. Francis, chief engineer of Proprietors of Locks and Canals.