Vacuum fusion techniques by using nickel baths at both 1600°C and 1800°C, and nickel-tin bath at 1600°C were examined to determine oxygen content in molybdenum, and solid diffusion extraction at 1800°C was also examined in order to determine both nitrogen and hydrogen contents.
The reproducibility of analysis of experimental one-gram sample was ± 1 part per million by weight for both oxygen and nitrogen contents below about 30 ppm. of oxygen and 10 ppm., of nitrogen, and ± O.1 ppm. for hydrogen content below about 1.0 ppm., in every technique above mentioned. And, it was seen that almost no difference was found between any results of oxygen analysis by the above bath techniques, while the results of both nitrogen and hydrogen analyses by these bath techniques were smaller than those by the solid diffusion extraction techninque.
Although every result of oxygen analyses by these bath techniques agrees very much with one another, these results of microanalysis are considered to show smaller value than that contained in the sample actually, receiving the effect of sorption of evolved carbon-monoxide gas by the film or vapor itself evaporated from the bath metals. In order to verify this effect, platinum and platinum-nickel bath techniques were examined. These will be described in the following paper with some conclusions of this experiment.

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