bon tetrachloride layer is shonn in Figure 6. Peaks 5, 9, and 10 decreased. On closer observation, it can be seen that peak 10 has shown a smaller decrease than either peak 5 or peak 9. The peak heights of components 9 and 10 are reversed after extraction. The carbon tetrachloride layer mas extracted once more nith propylene glycol. Figure 7 shoii s the chromatogram of the second carbon tetrachloride eLtract. Peaks 5 and 9 have decreased greatly and are almost absent. Removing most of component 5 has shown the presence of a minor component, which was not resolved in the original chromatogram. Peak 10 shows only a very small decrease after the second extraction. This fact indicates that peak 10 is actually composed of more than one component, one of mhich must be an alcohol. The major portion of this compound was removed in the first extraction. The other component of peak 10 has been identified as geranyl formate by its retention time.To establish the identity of the three alcohols, the infrared spectra of both the layers of the initial extraction mere run and are shown in Figure 8 To find out nliich bands in the spectrum are due to alcohols, one chooses those bands that are stronger in the propylene glycol layer. These bands appear a t 2. 90, 9.00, 9.45, and 10.05 microns. The band a t 9.00 microns is due to linalool. The band a t 9.45 microns is due to citronellol, and a t 10.05 microns, the band is assigned to geraniol. The bands a t 9. 75, 5.82, 7-95, 8.15, 8.55, and 11.25 microns appear much stronger in the carbon tetrachloride layer. These bands must be due to esters, ketones, or terpenes.The band a t 5.75 microns has been assigned to the esters, and the one a t 5.85 microns to menthones. The bands a t 7.95 and 8.15 microns are assigned to citronellyl acetate and geranyl acetate, respectively. The band a t 8.55 microns is due to citronellyl and geranyl formates. The band a t 11.25 microns is due to terpenes. The infrared spectra of the extraction layers enable one to determine which bands in the original spectrum are due to alcohols and which are not. If there is doubt concerning any band because of almost equal intensity in both layers, this can be resolved by looking a t the spectra of further eutractions. The infrared b A gas chromatographic method has been developed for the determination of small amounts of dissolved gases in aqueous solutions. The equipment consists of an all-glass sample chamber in which the dissolved gases are stripped from solution b y an inert carrier gas, a four-way by-pass valve, a commercially available gas partitioner, and a 1-mv. recorder. Calibration for routine work is accomplished b y carrying out the determination on a sample of water saturated with pure gas at a known temperature and pressure. At present, the method is capable of determining dissolved gas concentrations as low as 0.3 p.p.m. in 1 -to 2-ml. samples of solution.
