Sellos

joseph von fraunhofer (6 march 1787 - 7 june 1826) was a german optician. he is known for the discovery of the dark absorption lines known as fraunhofer lines in the sun's spectrum, and for making excellent optical glass and achrom

matthaus daniel poppelman (may 3, 1662 - january 17, 1736) was a german master builder who helped to rebuild dresden after the fire of 1685.

der blaue reiter (the blue rider) was a group of artists. the group was founded by a number of russian emigrants, including wassily kandinsky, alexej von jawlensky, marianne von werefkin, and native german artists, such as franz ma