SMITHSONIAN REPORT, 1901. ABBOT. 



PLATE IV 



LUNAR CRATER THEOPHILUS AND SURROUNDING REGION. 



PHOTOGRAPHED BY G. W. RITCHEY, WITH THE FORTY-INCH VISUAL TELESCOPE, YERKES 



OBSERVATORY. EXPOSURE ONE-HALF SECOND. 



SCALE ABOUT 1 METER TO LUNAR DIAMETER. 



