Though as Captain Brown points out nothing is more fatal to the mole than excessive rain, which fills their subterranean galleries with water; the following statement made by Mr. A. Bruce in the Linnæan Transactions, shows that the animal is not without enterprise on the water:--"On visiting the Loch of Clunie, which I often did, I observed in it a small island at the distance of one hundred and eighty yards from the nearest land, measured to be so upon the ice. Upon the island, the Earl of Airly, the proprietor, has a castle and small shrubbery. I remarked frequently the appearance of fresh mole casts, or hills. I for some time took them for those of the water mouse, and one day asked the gardener if it was so. No, said he, it was the mole; and that he had caught one or two lately. Five or six years ago, he caught two in traps; and for two years after this he had observed none. But, about four years ago, coming ashore one summer's evening in the dusk, with the Earl of Airly's butler, they saw at a short distance, upon the smooth water, some animal paddling towards the island. They soon closed with this feeble passenger, and found it to be the common mole, led by a most astonishing instinct from the castle hill, the nearest point of land, to take possession of this desert island. It had been, at the time of my visit, for the space of two years quite free from any subterraneous inhabitant; but the mole has, for more than a year past, made its appearance again, and its operations I have since been witness to."
The use of the mole is often said to be far outweighed by the mischief he perpetrates, the truth appearing to be that like many other animals, in his own place he is valuable, out of it he is a source of danger. Both conditions are illustrated by the following, which I quote from Mrs. Bowdich's "Anecdotes of Animals."
"A French naturalist of the name of Henri Lecourt devoted a great part of his life to the study of the habits and structure of moles; and he tells us that they will run as fast as a horse will gallop. By his observations he rendered essential service to a large district in France; for he discovered that numbers of moles had undermined the banks of a canal, and that unless means were taken to prevent the catastrophe, these banks would give way, and inundation would ensue. By his ingenious contrivances and accurate knowledge of their habits, he contrived to extirpate them before the occurrence of further mischief. Moles, however, are said to be excellent drainers of land; and Mr. Hogg, the Ettrick Shepherd, used to declare that if a hundred men and horses were employed to dress a pasture farm of 1500 or 2000 acres, they would not do it as effectually as moles would do, if left to themselves."