who invented fountain pen and in which year
Fountain pen Progress in developing a reliable pen was slow until the mid-19th century because of an imperfect understanding of the role that air pressure plays in the operation of pens. Furthermore, most inks were highly corrosive and full of sedimentary inclusions. The Romanian inventor Petrache Poenaru received a French patent on May 25, 1827, for the invention of the first fountain pen with a barrel made from a large swan quill.[8]
Rotary dial The first patent for a rotary dial was granted to Almon Brown Strowger (November 29, 1892) as U.S. Patent 486,909, but the commonly known form with holes in the finger wheel was not introduced until ca. 1904.[citation needed] While used in telephone systems of the independent telephone companies, rotary dial service in the Bell System in the United States was not common until the introduction of the Western Electric model 50AL in 1919.[1]