Moncure Daniel Conway 
Demonology [EPUB ebook] 

Three Friars, says a legend, hid themselves near the Witch Sabbath orgies that they might count the devils; but the Chief of these, discovering the friars, said-‘Reverend Brothers, our army is such that if all the Alps, their rocks and glaciers, were equally divided among us, none would have a pound’s weight.’ This was in one Alpine valley. Any one who has caught but a glimpse of the world’s Walpurgis Night, as revealed in Mythology and Folklore, must agree that this courteous devil did not overstate the case. Any attempt to catalogue the evil spectres which have haunted mankind were like trying to count the shadows cast upon the earth by the rising sun. This conviction has grown upon the author of this work at every step in his studies of the subject.