General view of Wilson Walker, Chief Chemist at the Ohio Department of Health's Sanitary Chemistry Laboratory, injecting a sample of drinking water into the cylinder of a Perkin-Elmer Heated Graphite Atomizer (HGA). Per notations accompanying the photograph, the vaporizing furnace serves to atomize the sample molecules for analysis by the Perkin-Elmer Model 403 Atomic Absorption Spectrophotomter located on Walker's right. The analysis was conducted to detect the presence of heavy metals, including cadmium, copper, arsenic, tin, and silicon in particular, in the state's water supply.