Samuel Morey - Experiments With Vapors and Combustion

Experiments With Vapors and Combustion

In an 1834 letter to Professor Benjamin Silliman Morey writes, “It is now more than twenty years since I have been in the constant, I may say daily practice of making experiments on the decomposition of water, by mixing with its vapor that of spirits of turpentine, and a great portion of atmospheric air.” This would seem to understate the scope of some research that led to such diverse discoveries as the liquid fueled internal combustion engine, a method for carbonating water, and odd bubbles formed by molten resin. The last two appeared in journals in England and Germany, respectively.

Morey noted differences in flames near knots, perhaps rich in sap, or in wet wood. Eventually he experimented with anything he could find: “tar, rosin, rough turpentine, or the spirit, or alcohol, or any kind of oil, fat, or tallow; mineral coal, pitch-pine wood, and the knots, birch bark, pumpkin, sun-flower, flax, and other seeds; as well as many other substances.”

His experiments are described at length over several articles in the American Journal of Science and Arts. They are light on theory, and Silliman comments that “ results are often very valuable, and perhaps, in some cases, not the less so, for having been sought without the direction of preconceived, theoretical views.” This is mostly true; theory enters into these articles mostly for possible explanations. However, in 1834, 15 years after his first publication on the subject, he proposes a theory of combustion that has electricity as its basic force. Hints of this theory may be visible in his first paper, but his early experiments were not guided by it.

His first practical application was to heat water for his revolving engine. He observed that passing steam over burning coal or tar caused the flames to burn brighter and without smoke, and he theorized that the steam was decomposed in this process. Word of these experiments reached the eminent French chemist Gay-Lussac, and he commented on them in Annales de Chimie et de Physique in 1819. He contended that the temperature was insufficient to cause decomposition. Instead, the steam freed more flammable vapors in the fuel causing the flame’s change.

It turns out that Morey was correct. He produced what is now known as town gas. The oxygen from the water combines with carbon from the fuel to form carbon monoxide and the hydrogen forms a diatomic molecule. Both later burn to form water and carbon dioxide. Morey was not the first to use water-gas for lighting, and his devices, including the patented 1818 American Water Burner, simply used the gas immediately instead of piping it to be burnt elsewhere, done as early as 1792 in England. It seems that Morey did not know of this advance or at least did not recognize it as the same process. Strangely, in 1819 J. F. Dana of Dartmouth and Harvard proposed attaching steam boilers to street lamps to take advantage of Morey’s discovery, but water-gas was already being piped to some London street lamps from a central source in 1812. Still, Morey’s device did produce more light, and there is evidence that it resulted in more efficient combustion.