Design of a precise theodolite

The Coast and Geodetic Survey has experienced so much difficulty in the past few years in obtaining satisfactory first‐order theodolites, and by this I mean instruments which can be read to one second of arc, that we have decided to design an instrument ourselves which will embody the various desirable features of existing theodolites, and also such other characteristics as our field experience has indicated will aid in making a more rugged, portable, and easily operated instrument. Briefly, the essentials of a theodolite such as we need are lightness, ruggedness, a perfectly graduated circle, frictionless centers, and perfect optical qualities. Perfection, of course, can only be approximated.