Why did Mary Baker Eddy write the Manual of The Mother Church?

Mary Baker Eddy wrote the Manual of The Mother Church to establish a coherent institutional structure for the Christian Science movement and to provide a governing authority for the church following her death.1

First published in 1895 and revised over the subsequent 15 years, the manual outlines the laws, organization, and activities of the church. It created a federal framework that balanced the authority of a five-member, self-perpetuating Board of Directors—entrusted with executing the manual's provisions—with the distinctly democratic character of the self-governing branch churches worldwide.12