But when men and horses, cattle, camels, and dromedaries, have poached the spring into mud, it becomes loathsome to those who at first drank of it with rapture; and he who had the merit of discovering it, if he would preserve his reputation with the tribe, must display his talent by a fresh discovery of untasted fountains.

If the author, who finds himself limited to a particular class of subjects, endeavours to sustain his reputation by striving to add a novelty of attraction to themes of the same character which have been formerly successful under his management, there are manifest reasons why, after a certain point, he is likely to fail. If the mine be not wrought out, the strength and capacity of the miner become necessarily exhausted. If he closely imitates the narratives which he has before rendered successful, he is doomed to “wonder that they please no more.” If he struggles to take a different view of the same class of subjects, he speedily discovers that what is obvious, graceful, and natural, has been exhausted; and, in order to obtain the indispensable charm of novelty, he is forced upon caricature, and, to avoid being trite, must become extravagant.