that gives as a chance to talk about the historic efforts, and on display are two pre-columbian, peruvian skulls. these are hundreds of years old showing evidence of trepanation. it is a drill to relieve pressure in the brain. we contrast these two skulls from peru with the skull of a civil war soldier showing essentially the same type of surgical treatment. we then give the visitor a chance to see the types of tools used, and at the end of the exhibit, an opportunity to see the types of tools used for modern t.b.i. rehabilitation which includes interestingly , enough, video games, and the important role that service animals play in helping t.b.i. patients recover and go about their daily lives. so, we have come to the third of the three exhibit galleries. we have moved here to an exhibit on biomechanical engineering which features this artificial kidney. the kidney here was invented by a dutch physician who developed this technology in nazi occupied holland. the first generation of this device was built using scrap parts from downed german airplanes and leftover kitchen utensils. when the docto