George Adelmer 1852- Rogers

$Skiascopy : A Treatise on the Shadow Test in Its Practical Application to the Work of Refraction : with an Explanation in Detail of the Optical Principles on Which the Science Is Based$ Skiascopy : A Treatise on the Shadow Test in Its Practical Application to the Work of Refraction : with an Explanation in Detail of the Optical Principles on Which the Science Is Based