I shall also be away from Berkeley during the vacation period in July and possibly part of August. Under these circumstances the earliest date on which I could receive you in Berkeley would be September 1, 1957 [...]“. – Daniel Arnon war seit 1946 Assoc. Prof. für Zellphysiologie an der University of California. „Arnon’s most famous work centered on photosynthesis. In 1954 he and his colleagues used components from spinach leaves to achieve photosynthesis in the absence of whole cells. This experiment helped explain how plant cells assimilate carbon dioxide, a necessary component in photosynthesis, and form adenosine triphosphate (ATP), a molecule that acts as a carrier of energy. Arnon hoped that scientists would eventually be able to duplicate the process of photosynthesis in the absence of plants, thus ending humans’ dependence on crop plants for food“ (msn.encarta). – Auf Briefpapier mit gedr. Briefkopf; mit kleinen Läsuren am linken Rand..