A passion for portraits: Elizabeth Cay's pastels

Elizabeth Cay (1771–1831), the grandmother of the Scottish physicist James Clerk Maxwell (1831–1879), was a talented amateur pastellist; several of her pastel portraits survive as does her set of pastels. She studied with Archibald Skirving (1749–1819), a Scottish miniature painter who later in life turned to larger-scale portraiture in pastel and served as drawing master to the Edinburgh elite. Cay's pastels are not fabricated sticks but consist of powdered pigment housed in various glass and ceramic containers and were apparently applied by stumps, still in her workbox, or brushes. The Cay color samples were identified by spectrographic analysis, polarized light microscopy, and microchemical tests which, in addition, indicated that a number of pigment mixtures present gave specific hues in keeping with earlier treatise accounts of the preparation of a pastel gamut for practical use. Elizabeth Cay's pastel workbox may be rare surviving evidence of one way, more common that we appreciate today, in which amateurs, and perhaps professionals, practiced pastel painting.     

The CoVis Project: Building a Large-Scale Science Education Testbed*

This paper describes the construction and research program of the Learning Through Collaborative Visualization (CoVis) Project, a testbed for exploring science education reform with telecommunications technology. The CoVis testbed is contrasted with other forms of educational research in an “ecology of paradigms,” which argues that testbeds are in fact a new setting for research with different requirements and challenges for the researcher. Two extended examples of telecommunications research are provided as examples of the kind of research that testbeds are well suited to explore. The first example is the evolution of videoconferencing in the CoVis testbed. The second example is the design and development of a networked groupware application called the Collaboratory Notebook.