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The absolute infrared intensities of the two fundamental vibrations of each of these ions have been measured in the pure sodium salts using reflection techniques on pressed pellets. In addition, the corresponding absolute intensities for $BF4$ have been measured in dilute solid solutions of KBr. The results are (in units of $103$ darks): pure $NaBH4,A(\nu 3)=90,A(\nu 4)=17.2$; pure $NaBF4,A(\nu 3)=203,A(\nu 4)=3$ (rough value); $BF4-$ in KBr. $A(\nu 3)=132,A(\nu 4)=2.0$. These results together with previous $work1$ on $BH4-$ in KBr show that the absolute intensities in the pure substances tend to be substantially higher than those in solid solution. Supported by the National Science Foundation.