7 7 2 D O C . 4 8 5 O N T H E T H E O R Y O F L I G H T Published in Revista da Academia Brasileira de Sciencias (1926): 1–3. [1]Lecture delivered on 7 May 1925 at the Brazilian Academy of Sciences. For a transcription of the original German manuscript [83 865], see Doc. 484 (the preceding document). For a historical dis- cussion, see Tolmasquím and Moreira 1995.