- The Armsby Respiration Calorimeter:Forming Food Animal Foodways
animals, Armsby, calorimeter, feed, nutrition
New investigations in science can redefine and reconstitute our food-ways. This is perhaps best illustrated in the twentieth-century development of the nutritional sciences, where increased attention to caloric energy and the discovery of vitamins shaped food consumption and labeling in the United States.1 Such studies not only affected how humans ate; they also influenced the foodways of the nonhuman animals integral to human food systems. Pennsylvania State University's Armsby Respiration Calorimeter was one technological site for such investigations. Still sitting in a small brick building on the northern side of Penn State's campus, the calorimeter helped shift international understandings in how to feed beef and dairy animals. It became not only a national monument of agricultural progress in the early twentieth century but also a space to test renewed understandings of nutrition over the course of the century.
Henry Prentiss Armsby proposed building a respiration calorimeter at Pennsylvania State College to the United States Bureau of Animal Industry in 1898.2 The first device of its kind in the world, the calorimeter measured the body heat, respiratory intake, and gaseous outputs of livestock to determine feeding efficiency. It was a central part of Penn State's Institute of Animal Nutrition, which went on to publish college-affiliated and federal bulletins on various aspects of animal metabolism and the conversion of feed for meat and milk production. National organizations, including the Federal Trade Commission, used calculations from the calorimeter to support the regulation of specific animal feeds. The calculations helped determine misbranding in accordance with the 1906 Pure Food and Drug Act, and they helped alleviate commercial feed controversies about processing standards. These included investigations into feed mill testimonies that claimed milled oats were better for animal production than unprocessed oats.3 [End Page 393]
In addition to promoting early twentieth-century commercial feed standards, Armsby's efforts with the calorimeter were credited with inspiring the development of the United States Bureau of Animal Industry's Animal Husbandry Division.4 The device was so significant at this time that in preparation for the World's Dairy Congress, hosted by the United States in 1923, legislators suggested that the Armsby Calorimeter be one important "excursion site" for international visitors.5
Through the 1960s, the calorimeter acted as a stage where scientists played out larger questions asking how certain bodies processed certain foods. While its initial experiments focused on livestock, later studies included collaborative projects with Penn State's Foods and Nutrition Department. Students volunteered to be human subjects in mid-twentiethcentury experiments that compared food rationing and energy maintenance results initially found in mice.6 The inside of the calorimeter was altered to accommodate a bunkbed for two male students to occupy over a weekend (fig. 1). The calorimeter was later home to a hundred-gallon tank filled with microbial cultures from a cow's rumen.7 The device was sensitive enough to measure the energy exhausted by some of the smallest organisms known today; the measurements contributed to better understandings of how the rumen microbes in livestock processed food and converted it into bodily energy. By the 1970s, net-energy values—including those calculated using the calorimeter—became an important way to understand animal feed and feeding.8 They continue to help farmers and feed companies develop balanced rations for food animals today.
Scientific instruments like the calorimeter materialize the impact of science—in this case, university-developed and federally promoted knowledge—on our larger foodways. The calorimeter is also an historical artifact that challenges the boundaries scholars use to create our narratives about [End Page 394] food. Many food histories focus on the human interactions within larger food systems, but there are many organisms that contribute to food production and consumption networks. Humans, animals, and microbes all inhabited the calorimeter as individual and collaborative subjects, and all of their bodily interactions with certain kinds of food were observed and measured as meaningful in the context of scientific inquiry. When crafting the story of Pennsylvania's food history, it is important to consider when these historical actors became significant...