The Geology of the Darling Scarp at Ridgp: Hill. 
]2l 
Table IV. 
First, second {^Median) and third quartiles and coefficients of sorting (So) and 
skewness (Sk) of sands of Table HI. 
Sample. 
Q3 
IM 
Q1 
So 
Sk 
(mm.) 
(mm.) 
(mm.) 
A. 
■469 
■341 
•225 
1-444 
■907 
E. 
•417 
■243 
■ 130 
I -791 
■918 
0. 
■450 
•318 
■194 
1-523 
•863 
E. 
-.384 
•263 
■172 
1-494 
■9.54 
^dieients of skewness (Table IV). If the secondary allophanoid of the 
feio’uginous .sainkstone be disregarded it will be seen that the grading of 
the detrital niat(‘rial of tlie feri'uginons sandstone is of still higher degree 
than tliat of the yellow sands. The mechanical analyses indicate that 
^yRADE ^ ^ ^ 
ttrrr.) (T. cj ^ Q 
(T) 
<T2 
^ADE 
(fnTn) 
7r 
.4L . _ 
Text tig. 5. — Histograms showing: — (1) Mechanical composition. (2) Heavy 
mineral content. (3) Average visual projection roiindness in different 
grades (.10 grains niea.siu’cd in eacli gj-acle). (4) Average visual projection 
sphericity in different grades (oh grains measured in eadi grade) of: — 
A. Yellow sand, Crawdey, W.A. (22804). 
E. Yellow sand, Ridge Hill, W.A. (21364). 
C. Yellow sand, Ridge HUl, W.A. (22802). 
E. JnsoluOle revsidue in ferruginous sandstone, Ridge Hill, W.A. (22798 j. 
