TABLE OF CONTENTS.

I. Introduction........................................    1

II. Review of Previous Work in Visual Acuity.............    6

III.  Preliminary Study .................................. 15

IV.  Main Observations in Acuity.......................... 24

V. Supplementary Observations.......................... 31

VI. Discussion of Results................................ 35

VII. Color Photometry ...................................41

VIII. Conclusion........................................... 58
 

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