Limnology zoologist) and Einar Naumann (a Swedish botanist) co-founded the International Society of Limnology (SIL, from Societas Internationalis Limnologiae). Forel's original definition of limnology, "the oceanography of lakes", was expanded to encompass the study of all inland waters, and influenced Benedykt Dybowski's work on Lake Baikal. Prominent early American limnologists included G. Evelyn Hutchinson, Ed Deevey, E. A. Birge, and C. Juday. Physical properties of aquatic ecosystems are determined by a combination of heat, currents, waves and other seasonal distributions of environmental conditions. The morphometry of a body of water depends on the type of feature (such as a lake, river,
By the Light of the Study Lamp endpages. The series drew interest again so subsequent volumes were updated and released, with spine symbols, until the publication of a new volume (already written and set for printing in 1945) in 1952; new volumes were released once a year. In 1962, the Dana Girls switched to cream or beige spined picture covers, and went out of print in late 1968. "By the Light of the Study Lamp" was allowed to go out of print at that time. By the Light of the Study Lamp By the Light of the Study Lamp is the first book in The Dana Girls