That the world-famous ‘thinking horses’ of Elberfeld are not fakes, that they extract cube roots, read and spell by rational processes rather than by means of trick signs from their trainer, is the conclusion reached by one of the leading European authorities on animal psychology …

The cube root of 5832 was proposed by one of the ladies present, written on the board for the horse and the answer, 18, given correctly in a few seconds. and were likewise given correctly — 124 and 26 in about ten seconds. Mr. Krall and the attendant groom had left the hall immediately after the exercise was written on the board in each case. …

[ ]. Correct reply in a few seconds: 28. The horse was then alone in the room. All the spectators had also gone outside.

[ ]. Reply after 30 seconds: 117. Wrong. The horse corrected it himself to 144, but finally gave up rather despairingly.

— “Can Horses Think? Learned Commission Says ‘Perhaps,'” New York Times, Aug. 31, 1913