These two follow the same pattern of What's Inside of Me? and What's Inside of Plants? (1952, p. 450) and maintain an excellent beginning science book standard. First comes the pictured question, then the inside view. Facing the latter is a page in large print of simple, basic facts that first readers can understand and facing the former a more detailed and enlarged explanation in smaller print and double columns- which will need interpretation for starters, but do not in themselves contain enough to satisfy an eight to eleven group (hence the read aloud classification for these). What's Inside of Animals, illustrated with colored diagrams and drawings by Herschel Wartik, contains a division between animals with and animals without backbones, and the field covered includes earthworm, clam, grasshopper, fish, dog and so forth. What's Inside of Engines? similarly illustrated by Raymond Perlman, runs the gamut neatly from stream to jet. In both books drawings supplement as well as overreach the text, thus making them mutually additive, solid onceovers, and productive question grounds.