And a kittenâs teeth first come in between two to four weeks; their more permanent set appears at around four months of age. So if you open a catâs mouth and find permanent, white teeth, the feline is likely to be around a year old. popular misconception is that cats age seven years (in human years) for each calendar year. In fact, feline aging is much more rapid during the first two years of life.
Sarah Boone (1832-1904) was an African American inventor who on April 26, 1892, obtained United States patent rights for her improvements to the ironing board.
Best known for having invented the automatic oil cup, during his life, he invented and sold 57 different kinds of devices and machine parts including an ironing board and a lawn sprinkler. His first invention was a lubricator for steam engines, U.S. 129,843, which issued on July 12, 1872..F. Duncan Sr., inventor of the Eskimo Pie, created the first U.S yo-yo fad. Invented the computer mouse and the first windows. The German physicist who invented the alcohol thermometer in 1709 and the mercury thermometer in 1714.