CONTENTS. 



No. Page. 



1. Units of linear measure, units of area expansion of steel tapes, and conver- 



sion tables chains to feet and feet to chains 5 



2. RediK-tion in latitude to south boundary of township, and corrections for 



convergency within a township G 



3. Traverse table, for the correction of random lines 7 



4. Traverse tables 8 



5. Correction of error in stadia wire interval 98 



6. Stadia coefficients, vertical rod 99 



7. Natural sines and cosines 106 



8. Natural tangents and cotangents 115 



9. Logarithmic sines, cosines, tangents, and cotangents 127 



10. Logarithms of numbers 172 



11. Convergency of meridians, and differences of latitude and longitude 199 



12. Azimuths of the tangent to the parallel 200 



13. Offsets from the tangent to the parallel 201 



II. Azimuths of the secant 202 



15. Offsets from the secant to the parallel 203 



1C. Lengths of arcs of the earth's surface 204 



17. Apparent time of sunrise and sunset 205 



18. Conversion tables, degrees to time, and time to degrees 206 



19. Sidereal conversions, and reductions to the local mean time of upper culmi- 



nation of Polaris 207 



20. Mean refractions in zenith distance 208 



21. Coefficients to apply to mean refractions for variations in barometer and 



temperature 209 



22. Coefficients for computing errors in azimuth, due to small errors in declina- 



tion or latitude 210 



23. Mean refractions in polar distance 211 



24. Trigonometric formulas for the solution of plane triangles 218 



25. Trigonometric formulas for the solution of stadia measurements, observa- 



tions for time, latitude, and azimuth, and problems in convergency 220 



