This technology was tried in the late 80's but faltered because the price of oil dropped. Known in many states as the Talking Book Library, there are statelibraries with local toll free numbers. These slopes are adjustable on most activecrossovers, allowing a very gradual change between two drivers to afarly steep change. Also lookingto restore or possible sell one that I have. He was a Fellow of the Linnean Society, a society concerned with certain species of plants.