Complete Inventions: The Galilean Telescope and its Rivals

     
 

 

This talk addresses the gap between the well-publicized invention of the Dutch or Galilean telescope in the Netherlands in September 1608, and the obscurity of Galileo Galilei's own acquaintance with news of the device.  It argues that Galileo, like a few of his contemporaries, initially assumed telescopic vision to have been achieved through one of several configurations of a lens and a mirror, rather than with a combination of a convex and concave lens enclosed in a tube.  It further suggests that he and at least one rival labored under such misapprehensions until early summer 1609, when they obtained either more accurate information or a crude version of the Dutch telescope itself.  The paper concludes with discussion of the fact that even after Galileo published his telescopic discoveries concerning the lunar surface, the Milky Way, the moons of Jupiter, and the sunspots, such findings were often associated with rumors of a telescopic mirror.

Eileen Reeves