A method of manufacturing magnetic heads is provided in which a slider and a back yoke are joined to form a magnetic head main body. However, when the new language has sounds that do not occur in the language from which the bootstrapping is to be done, bootstrapping does not produce good initial models and the new language data is not properly aligned to these models. The optical film has at least one positioning flange. A ball valve is positioned adjacent the bottom of the containment vessel, the ball valve, when in open position, adapted to be in fluid communication with a well bore and the containment vessel.