Under the heading of aptitude for buffoonery, I have thought proper to place such defectives as evince a talent for wit and humor of a low order, as is instanced in some of the historical court fools and buffoons.
After this short preface regarding the nature of the cases it is proposed to include in a description of idiots savants, examples of each kind will be cited under the appropriate caption.
Arithmetical Faculty.—Precocity and an extraordinary power of the faculty of mental arithmetic have been frequently noted in idiots.
Dr. Howe described an idiot with little use of language, yet with astonishing power of reckoning. If one's age were told him, he would give the number of minutes one had lived in a very short time.
Guggenbuehl observed an imbecile at Salzburg who would solve the most difficult problems in mental arithmetic with incredible rapidity. At one time the attempt was made to induce him to become a teacher of arithmetic, but as he could not understand his solutions of problems it was found impossible for him to explain them to others.
Atkinson noted an idiot woman with arithmetical faculty in excess whose only delight was to be occupied with questions of number.
Ireland mentions a boy at Earlswood with the arithmetical faculty. He could add and multiply three figures by three figures with lightning rapidity.
In a valuable study of Arithmetical Prodigies in the American Journal of Psychology (April, 1891), E. W. Scripture has collected thirteen examples of this aptitude. Six of these (Ampére, Gauss, Archbishop Whately, George Bidder, Safford, and Wallis) were men of eminence or genius who exhibited extraordinary precocity or aptitude in mathematics. The remaining seven cases are properly classified under the heading of this paper.
Tom Fuller, born in 1710, known as the Virginia calculator, was a native African, never knew how to read or write, but had phenomenal powers in arithmetic. Asked how many seconds in a year and a half, he responded in two minutes, 47,304,000. Asked how many seconds a man had lived who was 70 years 17 days 12 hours old, he answered in a minute and a half, 2,210,500,800.
Jedediah Buxton, an Englishman, born in 1702, was excessively stupid as a child, never learned to write his own name, had not even common intelligence in the ordinary matters of life, and whose mind never reached a development beyond that of a boy of ten years, was a marvelous mathematician.
Zerah Colburn, born in Vermont in 1804, was exhibited from the age of six as a mathematical prodigy. He was a backward