He loved Marguerite Lecomte, and taught her to engrave as well as himself.
In some places wood-carving has been brought to considerable perfection; and native artists know how to engrave on metal both by etching and the burin.
In 1828 James Wilson (author of the article Ornithology in the 7th and Wilson 8th editions of the present work) began, under the title of Illustrations of Zoology, the publication of a series of his own drawings (which he did not, however, himself engrave) with corresponding letterpress.
The original drawings for this map had to be done with exceptional neatness, the draughtsman spending twelve months on that which he would have completed in four months had it been intended to engrave the map on copper; yet an average chart, measuring 530 by 630 mm., which would have taken two years and nine months for drawing and engraving, was completed in less than fifteen months - fifty days of which were spent in " retouching " the copper plate.
But evidence bearing on the Stone age in Africa, if the latter existed apart from the localities mentioned, is so slight that little can be said save that from the available evidence the palaeoliths of the Nile valley alone can with any degree of certainty be assigned to a remote period of antiquity, and that the chips scattered over Mashonaland and the regions occupied within historic times by Bushmen are the most recent; since it has been shown that the stone flakes were used by the medieval Makalanga to engrave their hard pottery and the Bushmen were still using stone implements in the 10th century.