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.
Richard Arkwright is the person credited with being the brains behind the growth of factories. After he patented his spinning frame in 1769, he created the first true factory at Cromford, near Derby. This act was to change Great Britain. Before very long, this factory employed over 300 people.