IN preparing the material for a lecture on Charts for Columbia University, the writer was impressed with the fact that although nautical charts are mentioned or dis cussed in many publications, there was not found any one which covered the general subject of their origin, con struction, and use. In the countries of the world more than a million copies of such charts are now issued annually. A considerable portion of the human race is interested directly or indirectly, whether as mariners or passengers or Shippers, in navigation upon the sea. Aside from supplying a handbook for those who might have a general interest in the subject, it was thought that a discussion of charts might lead to further con sideration of the principles governing their construction. This paper has intentionally been made as non technical as seemed feasible in treating a somewhat technical subject. The writer is indebted to the Coast and Geodetic Survey for various illustrative material from its archives, and to a number of authors for facts or suggestions. A list is appended of books and papers which have been freely consulted, bearing on this and related subjects.