CADY AND MCFARLAND.| Composition of Natural Gas. 273 
Figure 7 shows these lines of nearly equal helium content and 
figure 8 shows the lines of nearly equal paraffin content. These 
lines, which may be called isohelium and isoparaffin lines, are 
suggestively similar to the lines showing the outcrop of the 
various geological strata in eastern Kansas.'® 
The explanation of this regularity of distribution is undoubt- 
MAP. sowing TOTAL PARAFFINS (CH,+Cot4) 
iw NATURAL GASES 
or KANSAS. 
a ‘ 
94.25 
KANSAS CITY 
97/8 »SHEFFIELO 
> BONNER SPGS b 92.9 
AVY OR f 
Lae 
nde 
ys 
/ 
/ / 
‘631 
EL ey 
ae sian ok 
MOLINE Ip 
4 4 
10 
PE Ru 
163. A map showing the latter may be found in vol. 111 of the Reports of the 
University Geological Survey of Kansas; plates 7 and 8, p. 106. 
—16 
- DEXTER 
l cs 
ARKANSAS C/ 
93.05 | 7 ]N 
/ 
BLACKWELL 
93.75 
@BARTLESVILLE 
Fie. 8. 
