Untitled (bleed-through of previous page, left page); Untitled (design for light work ["Foucault" pendulum], right page)

Graphite and colored pencil on artist's vellum (tracing paper)

Pastel on off-white wove paper

Graphite with green, blue and brown crayon on paper

Graphite on paper

Silk collage with acrylic paint and graphite mounted to cream wove paper

Gouache on illustration board

Colored marker on paper

Black chalk and gray wash, with a framing line in brown ink, on cream antique laid paper; figures at lower left and wash in sky at upper left are later additions

Charcoal on paper

Watercolor, black ink and graphite on cream laid paper

Graphite on paper

Graphite on cream antique laid paper