Over the past five years since its launch in winter 2015, the online journal of Klee studies, Zwitscher-Maschine, has published numerous essays and interdisciplinary contributions. Now we are pleased to publish our tenth issue. We would like to take this opportunity to express our sincere gratitude to all readers as well as those who have contributed to the journal so far. In particular, the publication of this issue would not have been possible without the support of Rita Klee. We would like to express our deepest gratitude to her for her invaluable assistance.

Paul Klee wrote to his friend Hans Bloesch in 1898: »But the most cursed thing is what you said about Klee and Bloesch philologists. One should almost write in a good style. But I don't want to [...]«. Klee saw himself early on as an object of later study. Now, for the first time, the correspondence between Klee and Bloesch has been published with an extensive commentary by Marcel Baumgartner. Oskar Bätschmann has written a scholarly review. The contribution by Wolfgang Kersten and Ginster Eheberg is concerned with Klee's illegitimate child, about which he informed only his friend Bloesch in 1900. Lilia Sokolova examines the Blue Four artists' group organized by Galka Scheyer from the expanded perspective of intercontinental cultural development. Marie Kakinuma's research of material related to Klee's »split« works sheds new light on the creative process, in which the works of his son Felix also played an important role. Thus, Kakinuma's essay opens the special contributions in this issue of the Zwitscher-Maschine. These also include the investigations by Livia Wermuth, Walther Fuchs, and Osamu Okuda.

We have succeeded in linking current exhibitions and research by adding a new section entitled »Workshop« with essays on the current research exhibition Paul Klee. I Want to Know Nothing (Zentrum Paul Klee, Bern, 8.5. to 29.8.2021; LaM - Lille métropole Musée d'art moderne, d'art contemporain et d'art brut, Villeneuve-d'Ascq, 19.11.2021 to 28.2.2022). We would like to continue this idea in future issues.

Last but not least, Eva Wiederkehr Sladeczek enriches her earlier contribution in the Zwitscher-Maschine with new knowledge about Klee's early work.

Beginning with this issue, we are also introducing the journal to a wider readership through the Zentrum Paul Klee's social media channels. Please see the links below (hashtag: #zwitschermaschine):

facebook.com/zentrumpaulklee
instagram.com/zentrumpaulklee
twitter.com/ZentrumPaulKlee

The editors:
Fabienne Eggelhöfer, Zentrum Paul Klee, Bern
Walther Fuchs, Digiboo Publishers, Küsnacht
Osamu Okuda, Zentrum Paul Klee, Bern

Cover image
Paul Klee
Drei weisse Glockenblumen, 1920, 182 Ölfarbe auf Karton, 26,5 x 19 cm Privatbesitz,
Deutschland
©Zentrum Paul Klee, Bern, Archiv