. Studies in natural history. Natural history; Natural history. 14 IOWA STUDIES IN NATURAL HISTORY. Fig. 2. Temperature, summer heat-income, and reduced thickness of Okoboji lake. The curve RT gives at any point the reduced thickness in centimeters (p. 8) of a stratum one meter thick whose center is at that point. The curve cal. gives the summer heat-income per meter of depth corresponding to the temperature curve. It is given in calories per square centimeter of the surface. It is derived from the two other curves by the formula (T-4): RT. See p. 12. is multiplied by the sum of the five RT's.
. Studies in natural history. Natural history; Natural history. 14 IOWA STUDIES IN NATURAL HISTORY. Fig. 2. Temperature, summer heat-income, and reduced thickness of Okoboji lake. The curve RT gives at any point the reduced thickness in centimeters (p. 8) of a stratum one meter thick whose center is at that point. The curve cal. gives the summer heat-income per meter of depth corresponding to the temperature curve. It is given in calories per square centimeter of the surface. It is derived from the two other curves by the formula (T-4): RT. See p. 12. is multiplied by the sum of the five RT's. The reason is obvious: The temperatures in the upper part of the stratum are above the mean and are multiplied by the larger num- bers representing the reduced thickness. The temperatures in the lower part of the stratum, which are as much below the mean as the others are above it, are multiplied by the smaller RT. The result is to make the sum of the calories greater in the 10 m. stratum by as much as 75; in the others the difference is small since the change of tem- perature is not so great. The larger amount is the more accurate, since it gives proper weight to smaller units of thickness, but in general the difference is not worth noting. In each case the summer heat-income of Okoboji lake would be stated as about 21,000 cal. in 1919. The more accurate total is convenient to use in discussing the distribution of heat. Employing single meters to 20 m. and 5 m. intervals below that depth, it is 20,933 Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original University of Iowa; State University of Iowa; Making of America Project. Iowa City, Ia
Size: 1787px × 1397px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectnaturalhistory, booky
