Sotls of the South-Western Districts of the Cape Colony. 139 
The foregoing samples are of too miscellaneous a nature to enable 
one to draw definite general conclusions, but it is noteworthy that 
the soils more or less affected by the underlying limestone, such as 
Nos. 25, 26, 29, 30, 33, are also proportionately richer not only in 
lime—as is but natural—but also in potash, than the other samples. 
The ultimate origin of the large amount of potash in soils of this 
nature is a point of some interest worth elucidating; it does not 
seem improbable that it is caused by the débris of granitic rocks 
being mixed with the compacted sand: from the blown sand the 
potash could certainly not be derived; least of all is such an idea 
plausible when we consider that the quantity of potash available in 
some of these soils ranges as high as 5 per cent. No. 29 is the only 
soil that can be called rich in phosphates ; Nos. 24, 25, 30, 32, and 33 
have a fair amount, but all the rest are decidedly poor in this respect. 
The sample No. 37, taken from above a small outcrop of granite 
in the Bredasdorp Division, is an alluvial sandy soil derived from the 
surrounding hills, which are composed of Table Mountain sandstone ; 
the amount of lime in this soil is satisfactory, and it has a fair quan- 
tity of potash, but is poor in phosphates. 
From the mass of granite which, commencing north-west of 
Mossel Bay, extends over a considerable portion of the George 
_ Division, two samples were taken on the farm Hartebeest Kraal 5 
they are numbered 38 and 39, the former a red and the latter a 
black soil. Both these samples contained a fair amount of lime, but 
No. 38 was very rich in potash, and indeed No. 39 was not unsatis- 
factory in this respect; the phosphoric oxide is moderate in amount 
in both cases. The preponderance of potash appears to be due to 
the felspar of the granite, but the question is still being investigated, 
inasmuch as a number of samples, taken further eastward, are at the 
present time under analysis. 
Turning now to the Malmesbury clay slate beds, 75 samples were 
collected and analysed; these were distributed as follows :— ) 
fe S 
S) SS) | Puiaee 7 
‘ ‘ é ca aed g o ty nee oo 
Name of Farm and No. 9 a a op See As 
of. Sample. s we = q 3 er aK 
, ’ La | 
oe a 5 oy 2 
Divis1oN—CaAPE 
Field-Cornetcy : Tygerberg 
and Kuils River 
AO, Maastricht ....50...00s006 1°33 | 15°50 | 054 | 128 | 48 | :045 | -028 
Ce Ee ee 2-97 | 10°52 | 057. | 201) -64 | -27 | -028 
AQs, MiVCESAA seccceccess eos oes 1:37 6°94 70053 | +134 | °39 12 "044 
Ae cee WM TSkko a6 ideas craps 75 | 64.) | OO28eintet 385 | -026| 062 
| iN) 
