E. M. Bounds 
Purpose in Prayer [EPUB ebook] 
With linked Table of Contents

The more praying there is in the world the better the world will be, the mightier the forces against evil everywhere. Prayer, in one phase of its operation, is a disinfectant and a preventive. It purifies the air; it destroys the contagion of evil. Prayer is no fitful, shortlived thing. It is no voice crying unheard and unheeded in the silence. It is a voice which goes into God’s ear, and it lives as long as God’s ear is open to holy pleas, as long as God’s heart is alive to holy things.