A certain number of letters from Blake's friends and acquaintances have been added to the collection, wherever they have seemed to give it greater coherence, or to shed new light upon his life and character; and for this purpose extracts have often been sufficient. The notes are intended partly to clear up any allusions to events or persons which might present difficulties to the reader, and partly to connect the letters with Blake's other writings, and to explain the ideas which they embody in reference to the whole of his work. They have been made as brief and serviceable as possible. The illustrations have been carefully chosen in regard to the text.