VI PREFACE. 



Since the sixth edition was published (1895), I have 

 returned from a hurried visit to South and East Africa, 

 and I think ft worth while to mention here one point that 

 not only applies to South Africa, hut also to many other 

 countries. It is that in localities where there is much flat 

 or slightly undulating land, as in the extensive Karoo, the 

 greater part of the country is really most imperfectly 

 prospected, simply because soil, drift, &c., conceal the bed- 

 rock. In Barberton district, which is hilly or mountainous, 

 geological formations are exposed, but this is not the case 

 in most parts of South Africa. That there may perchance 

 be many more auriferous " banket " reefs or quartzites con- 

 nected with, or distinct from, those already known to exist, 

 no one can dispute, and it is not unreasonable to believe 

 that in the future more diamond-producing mines in Orange 

 Free State or elsewhere may be discovered. It is true that 

 a slight elevation above a diamondiferous " pipe " formation 

 may, in some instances, have been noticeable ; at the same 

 time I have heard that in other instances the converse has 

 been the case, or the elevation was not apparent. 



In British Guiana, too, much flat land or forest land 

 covered with soil, containing the accumulation of vegetable 

 matter, has retarded discoveries. Of course an outcrop, 

 here and there, of hard rock such as quartz or quartzite 

 may be met with; however, not by any means always. 

 Therefore, especial attention should be taken to explore the 

 banks and beds of rivers and dry creeks, as not unfre- 

 quently detached pieces of quartz, &c., and sometimes the 

 lode or deposit formation itself, may be noticed in the river 

 or creek bed. 



There is another point which although it is mentioned 

 elsewhere in this book cannot be borne in mind too care- 

 fully, and that is, that the searcher after minerals should 

 not expect to find free gold or indications of a mineral 

 staring him in the face ; he should rather assume that these 



