caption: The image shows a page from a book with a drawing of a man's face on it. The text on the paper reads "German Patent 727,727 - Page 1". The man in the drawing has a serious expression on his face, and his eyes are focused intently on something in the distance. His hair is dark and his skin is a light shade of grey. He is wearing a white shirt and dark trousers. The background of the image is a dark blue, and the text is written in a bold black font.