This paper reports the spectrographic analysis of five trace elements in silica, using a.c. arc and cap electrode. By plotting two selected lines instead of one against log, concentration of the elements in question, calibration curves obtained are steeper in slope. The results thus found are precise. With this technique trace elements of the order 10^-4,-10^-2 per cent can be det0rmined. Average deviations do not exceed eight per cant.