sentences:  In the 18th century, editions of this work consistently outnumbered Defoe's "Robinson Crusoe" and Richardson's "Clarissa" and the gap grew wider as the century progressed.The work consists of imaginary letters from virtuous friends and loved ones, including a two-year-old child to his grieving mother, who have died, gone to heaven and wish to impart spiritual advice, mainly in the interest of making sure that the souls of friends and loved ones go to heaven.The subject matter of the letters consists mainly of moral dilemmas and contemporary issues; many of the letters are reminiscent of moral essays, while others are closer to the situations depicted in novels.