The building blocks of the IC are transistors, which started out as a plastic triangular wedge covered with gold foil slit in half at the wedge's tip. One side of the wedge serves as the emitter, the other as the collector. The irregular-shaped material directly under the wedge is germanium, which acts as the base. Gains in the current of up to a hundredfold may be attained with this device. This image is a recreation. (Image Source: Smithsonian, Stan Augarten)