BRICKEARTH. 
491 
Analyses of Fuller's 
Earth. 
A. 
B. 
C. 
D. 
E. 
F. 
Midford 
Blue 
Earth. 
Midford 
Yellow 
Earth. 
Woburn ' Woburn 
Blue Yellow 
Earth. Earth. 
Nutfield. 
Perth. 
Silica - 
54-0 
59-3 
60-0 
56-9 
58-66 
62-60 
Alumina 
18-6 
20-8 
15-2 
15-7 
17-33 
17-65 
Ferric oxide 
3-9 
4-2 
7-8 
9-5 
7-21 

Ferrous oxide - 
8 

1-7 
1 

1-84 
Lime - 
7-0 
2-5 
2-7 
2-1 
3-17 
2-55 
Magnesia 
2-3 
1-9 
3-3 
2-7 
3-26 
2'05 
Soda - 
Potash - 
7 
1-8 

1-7 
*2 
6 
3 
7 
i- 1-63 
r 1-27 
1 0-50 
Carbonic acid - 
3-4 
3 

- 


Loss by ignition (besides 
carbonic acid) 
7-2 
8-6 
8-4 
11-9 
8'74 
10-95 
99-7 
99-9 
99-9 
99-9 
100-00 
99-41 
! 
The analyses A, B, C, D, were kindly made for the Geological Survey 
by Mr. Player in 1890. The Earths were dried at 100 C. 
In the Blue Midford Earth the iron is to a large extent peroxidized, in 
the yellow earth it is altogether so. 
In the Woburn Earths there is no Carbonate of Lime, considerably 
more iron and less alumina than in the Midford Earths. Moreover the 
difference in colour between the Blue and Yellow "Woburn Earths does 
not appear to be explained by their difference in composition. 
The analysis E is one of the purified Fuller's Earths by Mr. Bernard 
Dyer, July, 1885. 
The analysis F is by Mr. Charles Tookey (1863) of clay used for fulling 
cloth at Duncrab Keltic, near Perth. He observes that the presence of 
free Alkali in this clay, was shown by moistening it on red test-paper, 
when the paper was rendered distinctly blue. 
Other analyses of Fuller's Earths, from Nutfield, and from Yrongoch, 
Ehiwlas, have been published by Mr. P. Gerald Sanford.* 
Brickcarth, Potter's Clay, fyc. 
In both Inferior Oolite Series and Groat Oolite Series, clays 
are met with that are found serviceable for the manufacture of 
bricks, tiles, &c. ; and locally there are clays that have proved 
valuable for terra-cotta ware, and as fire-clays. 
Some of the clays contain a good deal of *' Race " or " Ranee," 
small concretions, often septarian, of carbonate of lime ; these as 
* Geol. Mag., 1889, p. 455; 1893, p. 160. See also J. Brierly, Proc. Hampshire 
Field Club, 1891, p. 84. 
