We study the column densities of neutral atomic , molecular , and warm ionized Galactic gas through their continuous absorption of extragalactic X-ray spectra at |b| > 25 ^ { \circ } .
For { N _ { H, 21 cm } } < 5 \times 10 ^ { 20 } cm ^ { -2 } , there is an extremely tight relationship between { N _ { H, 21 cm } } and the X-ray absorption column , { N _ { H,x } } , with a mean ratio along 26 lines of sight of { N _ { H,x } } / { N _ { H, 21 cm } } = 0.972 \pm 0.022 .
This is significantly less than the anticpated ratio of 1.23 , which would occur if He were half He I and half He II in the warm ionized component .
We suggest that the ionized component out of the plane is highly ionized , with He being mainly He II and He III .
In the limiting case that H is entirely HI , we place an upper limit on the He abundance in the ISM of He/H \leq 0.103 .

At column densities { N _ { H,x } } > 5 \times 10 ^ { 20 } cm ^ { -2 } , which occurs at our lower latitudes , the X-ray absorption column { N _ { H,x } } is nearly double { N _ { H, 21 cm } } .
This excess column can not be due to the warm ionized component , even if He were entirely He I , so it must be due to a molecular component .
This result implies that for lines of sight out of the plane with |b| \sim 30 ^ { \circ } , molecular gas is common and with a column density comprable to { N _ { H, 21 cm } } .

This work bears upon the far infrared background , since a warm ionized component , anticorrelated with { N _ { H, 21 cm } } , might produce such a background .
Not only is such an anticorrelation absent , but if the dust is destroyed in the warm ionized gas , the far infrared background may be slightly larger than that deduced by Puget et al . ( 1996 ) .