Fire Quote by Hermann von Helmholtz
“Heat can also be produced by the impact of imperfectly elastic bodies as well as by friction. This is the case, for instance, when we produce fire by striking flint against steel, or when an iron bar is worked for some time by powerful blows of the hammer.”
![“Next came the Patent laws. These began in England in 1624; and, in this country, with the adoption of our constitution. Before then [these?], any man might instantly use what another had invented; so that the inventor had no special advantage from his own invention. The patent system changed this…” quote by Abraham Lincoln](https://sms4smile.com/quotes/img-quotes/449/abraham-lincoln-88_adoption_next-came-the-patent-laws-these-began-in_1828.jpg)
