When oil became scarce in the 1970s, New Mexico's solar industry quickly boomed and then busted. State tax subsidies had helped sell complicated new systems that sometimes didn't work, and by the mid-80s many people ditched their solar designs. In an effort to rebuild its solar industry, the New Mexico Natural Resources Department has published a colorful and easy-to-read 48-page book, The New Mexico Home Solar: A Source Book, written by Ingrid Kelley. Kelley says what endured were simpler passive solar designs that save both energy and money, and her guide introduces home-builders to these time-tested techniques. She describes how to make bricks from newspaper and walls from tires as well as traditional adobe techniques and how to choose a site and work with building codes. Photos and simple illustrations accompany her descriptions, and a glossary of building terms runs alongside the text. The final pages contain a list of solar building organizations, workshops, videos and a bibliography. To receive a free copy, write the Cooperative Extension Service, New Mexico State University, Box 3AE, Las Cruces, NM 88003 (505/646-3425).