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 was about this date that diamonds were discovered, but not until well in the seventies did that industry assume any importance. In the year 1887, which was prior to the production of gold upon any considerable scale, the output of diamonds had grown to 3,692,265 carats, valued at £4,126,288. The mines are of volcanic origin, the material containing the diamonds having been forced through the overlying strata. In some cases the surface has been denuded, and the diamonds distributed in the courses of rivers, where they are still found in comparatively small quantities. The great production, however, is derived from mining operations within the pipe or crater. The work of securing and disintegrating the blue ground, and of extracting the diamonds, involves the employment of extensive machinery and much labour.

The general activity awakened by the working of these mines upon a large scale was manifested in the imports and exports of the Cape Colony and Natal, which, combined for the year 1887, rose respectively to £7,300,055 and £8,915,988. After deducting the value of diamonds exported, it will be seen that in twenty years the exports had nearly doubled.

It will probably surprise the reader to learn that, from the date diamonds were discovered up to the end of 1903, the total value produced amounted to no less than £111,129,000. During that year the Transvaal made its first significant contribution to the South African export of diamonds, amounting to £239,752, won principally by the Premier Diamond Mining Company.

Besides the general stimulus given to trade through the working of the Griqualand West mines, their requirements necessitated the building of about 600 miles of railway, the terminus prior to their discovery being at Wellington, only forty-five miles from the coast. The completion of this line became the signal for an active railway policy in other parts of the Cape Colony. A considerable impetus was given to the commercial progress of the country by the