Residue method for common minor elements

A spectrographic method is described for the quantitative analysis of many minor elements in natural water. The excitation of the water residue using a direct-current arc provides a method for the detection of elements present in very low concentrations. The concentration of the elements is determined in percent of the dry residue. The results are readily expressed in parts per million by multiplying the determined percent concentration of an element by the dissolved solids content of the water sample. The method is flexible and can be applied to the analysis of water of variable composition and dissolved-solids content.