United States magnetic tables and magnetic charts for 1905

The present publication is the author's concluding one while in charge of the magnetic work under the United States Coast and Geodetic Survey from 1899‐1906. It portrays the state of the Earth's magnetic forces in the United States for the date January 1, 1905, and accordingly contains tables of the observed magnetic elements as far as available in the regions covered and their values when reduced to the common epoch. There are furthermore given graphical representations (magnetic charts Nos. 1–5) of the actual distribution of the magnetic elements—declination, dip or inclination, horizontal component of the total intensity of the Earth's magnetic force, the vertical component, as also the total intensity. The iso‐magnetic lines are shown in red on a base map of the scale 1/7,000,000, and on the first three are likewise added in blue the lines of equal annual change.