Journey On A Cloud: A Children's Book Inspired By Marc Chagall. One of artist Marc Chagall's most enduring paintings is the basis for this beautifully crafted children's book that tells an enchanting story. This book tells the story of the postman Zephyr, who lives in a little blue village in the mountains where nothing ever changes. A dreamer hoping for adventures, he travels on a cloud, embarking on a fantastic airborne journey that takes him to distant and colorful lands.