1820, Samuel Taylor Coleridge, letter to Hartley Coleridge in H. J. Jackson (ed.), Samuel Taylor Coleridge: Selected Letters, Oxford: Clarendon Press, 1987, p. 226, We proceed—(at a tortoise or pedicular Crawl, you will say—but believe me, dear Boy! there is no other way of attaining a clear and productive Insight […] [)]
Source: wiktionary