It is no coincidence therefore that one of the central figures of nebular research in the nineteenth century reveled in exquisite and detailed pencil drawings, made with an expert hand. And unlike in many other areas of nineteenth century science, where the kind of work that went into visualization was associated with perfecting nature, for instance, or with the abstraction from the appearance of the phenomena (as in diagrams, graphs, charts, outlines and schematics), in the case of nebular astronomy the tendency was to mimetically and minutely capture as much as was possible. We will, in fact, even encounter techniques used by Herschel in his detailed drawings of the nebulae that enabled him to avoid losing himself in the labyrinth of details that he attempted to see his way through, and this, again, with the aid of paper and pencil.

As has been suitably established, in many cases in the history of science the ways in which phenomena were pictorially represented often depended on the introduction and availability of new or improved instruments. But such instruments as the graphite pencil, if we begin to take them seriously as such, heralded not only new schools of drawing, with new ways of representing, gesturing and even positioning the body, but also altered the very acts of drawing, seeing and knowing. With the kind of care, precision, and «minute diligence» made available to a draughtsman, the world might be attended to and seen differently. Consequently, what I wish to emphasize throughout this work is that specific acts of drawing, exemplified in what follows by pre-published sketches of the nebulae, were used in order to see with, to see more with, to see differently with, to make out with, to tease out visual details with, and to explore or probe with.

It has long been known to art historians that a hand drawn study, a preliminary sketch, a scribble, or a finished drawing, permit an intimate entry point into a master’s «signature» style, in a way that painting, for instance, which tends to cover the movements of the hand and its unique strokes, may not. In many cases, an individual drawing’s own history, left behind in the traces made by pen or pencil, ink or graphite, is palpable to an expert examination, and contains within itself an immediate «record of a physical act.» As the art historian David Rosand has put it: «the drawn mark is the record of a gesture, an action in time past now fixed permanently in the present; recalling its origins in the movement of the draughtman’s hand, the mark invites us to participate in that recollection of its creation.» [6] Rosand goes on to accentuate the act of drawing’s dynamic «probing,» «groping,» «grasping,» and «exploratory» features. [7] It will become evident that the working images in the observing books of the astronomers behaved exactly in these dynamic ways as well.