Patents are the DNA of inventions, spawning entire new industries, businesses and economies. The giving away of patents by Toyota to spur development in hydrogen fuel, and by Tesla to help kickstart electric vehicle technology, are recent examples. A study by the Brookings Institution finds that the most productive periods in the United States occurred during the early 20th century and the Great Depression. The rate of patenting is nearly as high today as at any time in U.S. history. The most patents (per capita) came in 1916, 1915, 1885, 1932, 2010, 2011, 1931, 1883, 1890 and 1917. Here’s a look at some inventions from those years.