Peering into the Depths: Scientific Images of a Lake

Visualisation, constitution of objects, field sciences
Diagrams, tables, texts
approx. 1870 - 1925
Philosophy of Science, History of Science
Ecological research, lakes, limnology
Summary of:
Schwarz, A.E. (2003). Die Ökologie des Sees. Diagramme als Theoriebilder. (The Ecology of the Lake. Diagrams as Theory Makers.) In: Bildwelten des Wissens. Kunsthistorisches Jahrbuch für Bildkritik, 1, pp. 64-74.

Limnology, the ecology of inland waters, begins with the transformation from “the lake of ordinary experience” to the scientific object “ecological lake”. In the course of this process, the lake is appropriated not solely through observation but through action on the object. Work is done on the lake: measurements are taken, numerical values literally brought forth. The figures are arranged in tables, algorithms are applied, data are transferred to diagrams: the lake becomes a controllable and manipulable object.

This study looked at the period from 1869 to 1922. In 1869 nature researcher François-Alphonse Forel published an article in which the lake was described for the first time as an environment for organisms and thus as a whole, as a “system”. With the founding of the International Society of Limnology in 1922, the scientific disciplining of the lake was brought to completion. Whereas graphic representations were of no significance at all at the beginning of this scientific appropriation, they became more and more important as the lake progressed towards becoming established epistemically – ultimately more or less constituting the very identity of the discipline.

At least this is true of quite particular diagrams: the key point about the graph is that depth is displayed from top to bottom, so that parameters such as temperature and the frequency of plankton are shown running from the surface of the water down to the lake bottom. While this goes against the usual reading direction, scientific activity follows this directionality into the lake’s depths. To a certain extent this type of diagram represents the lake topographically, reproducing activity at the lake bottom and opening up the lake’s depths via this visual representation. The so-called depth ordinate forms the basis for the discipline of limnology.

The research object itself is also afforded stabilisation by means of visual representation in a diagram: the lake becomes a normalised expanse of water (also in the geometric sense of a bounded space) through the graphic image. The continuity apparent in this graphic space generates a homogeneity that is created through the linear linking of measurements; this homogeneity is what makes continuity in the lake conceivable at all. And this idea in turn is what makes it possible to “find one’s way” in the lake (a practical means of orientation), thus contributing ultimately to the stabilisation of “ecological lake” as an object of research.

A further aspect of this work that is interesting in both media and science studies terms is the debate about the representation of organisms found in the lake, which undergo a transformation from text to table to diagram. In the first limnological treatises, the number of organisms found was first given in number words as part of the running text; then, in the next stage, the number words were listed in a table, so that it was still not possible to undertake any calculations. In the stage after that, actual numbers were given which were eventually presented in columns and further condensed by applying particular algorithms. Later still a steadily growing number of parameters were added to the tables, represented using figures. The tables became increasingly complex and thus difficult to read. The move toward graphics facilitated a “new clarity”. Graphics offer a bird’s eye view of the data contained in a table: the data can be taken in at a glance; they form a whole, they create an image. To the trained eye, then, graphics are easier to read: phenomena that were merely readable in the table but not apparent are now made visible.