Following the ""what's inside?"" pattern of his former books in this group (see What's Inside of Me. What's Inside Engines etc.) Mr. Zim's next questions are ones like ""What's inside the stove?"", ""What's inside the faucet?"" and so forth. Subjects covered also include the electric light bulb, the toilet, the icebox, the furnace, the floors and walls and of course, the doorbell. Raymond Perlman's scientifically exact two tone drawings plus Mr. Zim's clear cut explanations to these puzzlers should answer many a why or wherefore. A very handy little text.