On the Construction of a Silvered Glass Telescope
 Fifteen and a half inches in aperture, and its use in celestial photography

by Henry Draper

"On the Construction of a Silvered Glass Telescope" by Henry Draper is a scientific publication written in the mid-19th century. This work provides an in-depth examination of the design and functionality of a silvered glass telescope specifically suited for celestial photography. It presents both the practical aspects of telescope construction and the underlying scientific principles. At the start of the work, Draper outlines the historical context of telescope development and shares his personal journey of creating a larger, improved instrument in America. He details the materials and processes involved in grinding and polishing mirrors, silvering glass, and constructing the telescope's mounting and components. The opening portion sets the stage for an elaborate discussion on the various challenges encountered in this endeavor and how each was systematically addressed through experimentation and innovation.