My original tumblr post was here. These images are a series by Christopher Appel. In sequence, they are (1) Zeppelin Girl, (2) Dinosaur Island, (3) The Posh, Posh Traveling Life, (4) Silverback, (5) Idol Pursuits, (6) A Wrong Turn at Yuggoth, (7) The Green Hand, and (8) Airship and Autogyro. The were originally posted on tumblr at notpulpcovers.