Joule
2 of the 7 encyclopedias on this shelf carry an entry for Joule. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
jool, James (1818-1889), an English physicist. He was a native of Lancashire. His father was a brewer. He was in part a self educated man, but came under the influence of the celebrated Dalton. His life work was a long series of experiments on the relations that exist between heat and energy. One of his experiments is easily understood. He attached a weight to a cord wound on an axle, and connected the axle with a series of paddles turning in a quantity of water contained in a reservoir, like a churn. As the weight descended, the paddles worked in the water. He found that the descent of the weight and the churning of the water heated the water. After making due allowance for loss of energy by friction and loss of heat by condensation, he decided that the descent of 772.55 pounds one foot, or one tenth that weight ten times as far, etc., would raise the temperature of a pound of water 1 deg. F. In other words, he established the doctrine, known as Joule's Law, that 772.55 units of mechanical energy are equivalent to 1 unit of heat . The converse of this statement is applicable to the operation of steam engines. The heat required in raising the temperature of a pound of water 1 deg. F. is capable of raising a weight of one pound 772.55 feet. The interchangeability of heat and work is called the doctrine of the conservation of energy. It applies as well to other forms of energy, as light and electricity. In accordance with Joule's Law the scientist can tell beforehand how much heat, light, or electricity a piece of coal is capable of producing, and how much work it can do. Joule received honors and membership in the leading scientific societies of the world, and in 1873 was made president of the British Association for the Advancement of Science. His leading doctrine was announced in a paper read in 1847 at Manchester, England.
Collier's New Encyclopedia (1921)
JAMES PRESCOTT, an English physicist; born in Salford, England, Dec. 24, 1818. He studied under Dalton the chemist, made researches into electromagnetism, about 1840 turned his attention to the subject of heat, and ultimately established the theory of the mechanical equivalent of heat. His published work consists mainly of papers read before the Royal Society, of which he was made a fellow in 1850, receiving its medal in 1852, and the Copley medal in 1870. He received in 1878 a civil list pension of $1,000 in recognition of his services to science. His most important achievement was that of settling the mechanical equivalent of heat, which established that the quantity of heat capable of increasing the temperature of one pound of water 1° F. requires for its evolution the expenditure of mechanical energy represented by the fall of 772 pounds through died in Sale the space of one foot. He , Oct. 11, 1889. See JOULE'S LAW.