Emmenegger's painting technique

Emmenegger used commercially available pre-primed canvases of various textures and origins as picture supports, of which he had several rolls in stock. From these he cut smaller sections and mounted them on stretchers. Until February 1904, he used to apply a second primer of lead white oil paint. He noted the ready-to-use supports in the list of canvases he kept in his painting technique notebook. Once he had decided on a support, he supplemented the entry with the work category and the work title.

During the time Emmenegger kept a logbook, between February 1901 and June 1905, his painting technique corresponded to what is now called "layered painting" (Figs. 1–3); for this he used the high-quality artist's oil paints of the Mussini variety. Other painting techniques do not seem to have appealed to him; he also showed no interest in tempera painting, which fascinated many of his contemporaries, even if often only temporarily.

He usually left this second primer to harden for a few weeks; before he began to paint, he washed it with soapy water, spirit of wine, turpentine, or benzene. The next day he executed the underdrawing with charcoal, which he fixed with shellac, or he transferred the outlines of an already existing motif with a tracing and so-called "indigo paper" (blue carbon paper). Immediately afterwards he began to underpaint. When he was not pressed for time, he let the underpainting, with which he always covered the entire picture surface, dry for several weeks. Then he washed it with soapy water or an organic solvent and covered the areas of color that had become dull during drying with a retouching varnish. He then "painted over" or "finished" the painting, sometimes mixing his Mussini colors with up to three different media. In between and at the very end, he applied additional layers of retouching varnish, especially to dull areas.

Emmenegger questioned almost every one of the above steps at some point. Was it necessary to apply a second coat of primer? Which primer application was the right one if a glaze was to be used? What was the best way to smooth a primer? Was it correct to apply a fixative to the charcoal underdrawing? Which painting medium resulted in which color effect? How could early shrinkage cracks be prevented? Which color mixtures remained stable? And was it advisable to apply a final varnish to a painting? - He recorded all these considerations in the logbook.
 

Fig. 1: Cross-section of a paint layer sample of the painting Solitude (VdL No. 37), photographed under a light microscope (bright field with crossed polarizing filters). The following layers can be seen from bottom to top: At the very bottom is the thick, commercially applied oil primer (1), followed by the thin second primer applied by Emmenegger (2). This is followed by the dark green underpainting (3), the thicker, lighter overpainting (4) and finally a thin layer of varnish (5).
Fig. 2: As Fig. 1, image taken under ultraviolet radiation (365 nm) in the light microscope. The varnish layer (5) can be recognized thanks to its fluorescence.
Fig. 3: As Fig. 1, material contrast image in the scanning electron microscope.