Northumberland. As Henry Silvertop he came in for the Lartington property. He was born in 1779 and married Miss Eliza Witham, niece and co-heiress of William Witham of Cliffe, Yorkshire, when he took the name and arms of Witham.
The method of cutting thin sections of rocks and fossils had just been invented by Nicol, and this gave Witham the opportunity for his investigations. His papers are illustrated by the botanist McGillivray, to whom he may have owed some further assistance. Indeed he made little pretension to botanical knowledge, but the opinions which he expresses strike one as remarkably sensible, and he must have been a man of sound judgment, at least in scientific affairs.
Witham was the first investigator of that most famous of fossils, Lepidodendron Harcourtii; of the Craigleith tree (now Pitys Withami), of the Lennel Braes trees (Pitys antiqua and P. primaeva}, of the Wideopen tree (Pinites, now Cordaites Brandlingi) and of Anabathra pulcherrima. It is curious to notice that the Craigleith tree, a manifest Gymnosperm, was at first (1829) regarded even by the great Brongniart as a Monocotyledon, while others imagined it to be a Lycopod. Witham, however, soon set this right. He always speaks with great respect of Brongniart, then just becoming the recognised leader of fossil botany. The following passage from Witham's memoir on the vegetable fossils found at Lennel Braes, near Coldstream, is of interest.
"Now, according to that gentleman's [Brongniart's] opinion, out of six classes...only two existed at that period [Carboniferous], namely the Vascular Cryptogamic plants, comprehending the Filices, Equisetaceae and Lycopodeae, and the Monocotyledons, containing a small number of plants which appear to resemble the Palms and arborescent Liliaceae. The existence, therefore, of so extensive a deposit of Dicotyledonous plants, at this early period of the earth's vegetation, appears to demand the attention of the naturalist."
Brongniart's "Monocotyledons" were no doubt Cordaiteae. Witham, we see, set the great man right as regards the antiquity of Dicotyledons, in which, of course, Gymnosperms were then included.