There are young students with no _a priori_ repugnance for the labours of external criticism, who perhaps are even disposed to like them, who yet are--experience has shown it--totally incapable of performing them. There would be nothing perplexing in this if these persons were intellectually feeble; this incapacity would then be but one manifestation of their general weakness; nor yet if they had gone through no technical apprenticeship. But we are concerned with men of education and intelligence, sometimes of exceptional ability, who do not labour under the above disadvantages. These are the people of whom we hear: "He works badly, he has the genius of inaccuracy." Their catalogues, their editions, their _regesta_, their monographs swarm with imperfections, and never inspire confidence; try as they may, they never attain, I do not say absolute accuracy, but any decent degree of accuracy. They are subject to "chronic inaccuracy," a disease of which the English historian Froude is a typical and celebrated case. Froude was a gifted writer, but destined never to advance any statement that was not disfigured by error; it has been said of him that he was constitutionally inaccurate. For example, he had visited the city of Adelaide in Australia: "We saw," says he, "below us, in a basin with a river winding through it, a city of 150,000 inhabitants, none of whom has ever known or will ever know one moment's anxiety as to the recurring regularity of his three meals a day." Thus Froude, now for the facts: Adelaide is built on an eminence; no river runs through it; when Froude visited it the population did not exceed 75,000, and it was suffering from a famine at the time. And more of the same kind.[115] Froude was perfectly aware of the utility of criticism, and he was even one of the first in England to base the study of history on that of original documents, as well unpublished as published; but his mental conformation rendered him altogether unfit for the emendation of texts; indeed, he murdered them, unintentionally, whenever he touched them. Just as Daltonism (an affection of the organs of sight which prevents a man from distinguishing correctly between red and green signals) incapacitates for employment on a railway, so chronic inaccuracy, or "Froude's Disease" (a malady not very difficult to diagnose) ought to be regarded as incompatible with the professional practice of critical scholarship.