Carburetor
The first carburetor was invented by Samuel Morey in 1826. The first person to patent a carburetor for use in a petroleum engine was Siegfried Marcus with his 6 July 1872 patent for a device which mixes fuel with air.
Wilbur Olin Atwater
With annual costs exceeding $10 thousand, the respiration calorimeter was considered a dream project for the 19th century. Atwater began the first of about 500 experiments in 1896. In fact, "he made history by establishing America’s first state agricultural experiment station at [Wesleyan]." He studied respiration and metabolism in animals and in humans. The calorimeter aided studies in food analysis, dietary evolution, work energy consumption, and digestible foods. It measured the human metabolism balance by analyzing the heat produced and metabolic rate by a person performing certain physical activities. With this machine, the dynamics of metabolism could be quantified and the balance between food intake and energy output could be measured. Atwater applied the first law of thermodynamics to his research: Energy can be transformed (i.e., changed from one form to another), but it can neither be created nor destroyed. Before Atwater's development of the respiration calorimeter, many experiments on calorie intake and expenditure had been conducted on animals. During this period, there was a widely held belief that the first law of thermodynamics applied to animals, but did not apply to humans because they were unique. Atwater demonstrated that whatever amount of consumed energy humans cannot use is left over and stored in the body. His findings thus established that the first law applied to humans as well as animals. Atwater's research and conclusions in this regard changed both how people thought about science and about humans.