On the arc spectrum of scandium

During the course of an investigation recently communicated to the Society upon the spectra of certain rare earthy meteorites, a novel method was adopted to render these bodies sufficiently conducting to the passage of electricity to enable them to be used as electrodes for the production of an arc. As was then described, the method consists in powdering the substance, adding to it a certain proportion of finely-divided silver, and compressing the mixture into rods by means of an hydraulic press. I was in this way enabled to obtain the arc spectra of the meteorites without danger of contamination with any unknown impurity, as is the case when the usual method of burning the substance in the arc formed between carbon rods is resorted to. I intimated at the time that it would prove a useful means of producing the arc spectra of other refractory substances, and recently I have produced spectra of yttria and of several rare earths by this method. Having prepared a quantity of pure scandia from the mineral wiikite, I determined to examine its arc spectrum in this way.