Date of Award

Spring 1937

Degree Type

Thesis - Restricted

Degree Name

Master of Science (MS)




The investigation of the are and spark spectra of tungsten has been carried out by several independent groups. The most complete investigation is that by Exner and Haschek who give 4000 lines for the spark 3254 for the arc spectrum. In the following investigation of the arc spectrum, the lines of relatively high intensity in the visible spectrum, of which there are few, was the subject of study. The spectrum obtained from the ordinary copper arc in air contains a great many spark lines which are easily confused with the true arc lines. Experiments have been carried out by means of a three electrode arrangement whereby a sufficiently high density of metal vapor can be supplied, so that the arc can be maintained at voltages as low as six volts. In this manner the arc and spark lines have been completely separated. No attempt is made in this investigation along those lines nor is the object to get and measure a great quantity of lines. This study deals only with the lines of relatively high intensity in the visible portion of the ordinary arc spectrum. The lines of small intensity are best obtained from an arc of high amperage (20 to 30 amperes) and consequently will not appear on the plates contained in this work.