I learned about four inventions this week and they are the smallpox vaccine, the voltaic pile, the arc light, and Dalton’s Theory. First, I learned about the smallpox vaccine. Vaccine is a cure for disease and comes from cowpox virus. Jenner conducted numerous trials to convince the royal society. Second, I learned about the voltaic pile. The voltaic pile was the first electric battery. Batteries have a (+) and (–) terminals and electrons flow from (–) to (+). Third, I learned about arc light. The arc light is a lamp that produces a bright light generating an electric arc around two electrodes. The arc light replaced gas lighting and increased competition. Last, I learned about Dalton’s Theory. His first theory was that all matter is made of atoms. The second theory was that atoms with the same element are the same. His third theory was that compounds are combinations. Dalton’s theory has been changed over time.