This historic 1963 image depicts a starch block electrophoresis apparatus, which had been assembled, and made ready for a run. See PHIL 12024 for an unassembled view of the components. Note that at one end of the gel lane was a black wire, and at the other end was a white wire, which when activated, would maintain a continuous electric field from end-to-end of the lane. This charge would promote the flow of molecules that would travel from the negative pole to the positive pole. The uniformly dispersed electric field influences the movement of the molecules being separated, and the porous channels throughout the matrix allows smaller molecules to move more readily through the medium than larger molecules. This phenomenon of molecular migration, is measured base on time, thereby, giving the scientist an appreciation for the molecular components of a given substance being analyzed.