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Symbiotic stars are regarded as wide binary systems consisting of a hot whitedwarf and a mass losing giant. They exhibit unique spectral features at 6825\AA\ and 7082 \AA, which are formed via Raman scattering of\ion{O}{6}$\lambda\lambda$ 1032 and 1038 with atomic hydrogen. We adopt a MonteCarlo technique to generate the same number of \ion{O}{6}$\lambda$1032 and$\lambda$1038 line photons and compute the flux ratio $F(6825)/F(7082)$ ofthese Raman scattered \ion{O}{6} features formed in neutral regions with asimple geometric shape as a function of \ion{H}{1} column density $N_{HI}$. Incylindrical and spherical neutral regions with the \ion{O}{6} source embeddedinside, the flux ratio $F(6825)/F(7082)$ shows an overall decrease from 3 to 1as $N_{HI}$ increases in the range $10^{22-24}{\rm\ cm^{-2}}$. In the cases ofa slab geometry and other geometries with the \ion{O}{6} source outside the\ion{H}{1} region, Rayleigh escape operates to lower the flux ratioconsiderably. For moderate values of $N_{HI}\sim 10^{23}{\rm\ cm^{-2}}$ theflux ratio behaves in a complicated way to exhibit a broad bump with a peakvalue of 3.5 in the case of a sphere geometry. We find that the ratio of Ramanconversion efficiencies of \ion{O}{6}$\lambda\lambda$1032, 1038 ranges from 0.8to 3.5. Our high resolution spectra of 'D' type HM~Sge and 'S' type AG~Draobtained with the {\it Canada-France-Hawaii-Telescope} show that the flux ratio$F(6825)/F(7082)$ of AG~Dra is significantly smaller than that of HM~Sge,implying that 'S' type symbiotics are characterized by higher $N_{HI}$ than 'D'type symbiotics.

A Monte Carlo Study of Flux Ratios of Raman Scattered O~VI Features at 6825 \AA\ and 7082 \AA\ in Symbiotic Stars