The dog, Rolf, attained in the course of time to a higher level than did the horses. This may probably be explained by the fact that dogs are, as a rule, more continuously in the company of human beings, being also due to their superior intelligence. Rolf's mode of procedure consisted in a series of raps given with his fore-paws, similar to those given by the horses with their hoofs; but Rolf used the same paw for both decimals and units, so that we had from time to time to inquire after every number rapped out--'Is it a decimal or a unit?' Whereupon he would rap 'yes,' or 'no'--as the case might be. The numbers were then written down and the answers thus obtained. Rolf's feats of arithmetic, like those performed by the horses, included finding the square root in the most difficult problems; yet it was in the matter of spelling answers that he excelled. Indeed, he seemed to command a particularly rich vocabulary, and applied the same with the greatest accuracy and continuity, even in long answers. These replies, when collected in their proper sequence should provide us with a wealth of insight into an animal's life of feeling. Such a collection is already extant, but has not yet been made public. Many of the dog's answers, as well as innumerable debates about him have been published in the "Mitteilungen der Gesellschaft fuer Tierpsychologie"[2] ("Communications of the Society for the Study of Animal Psychology"), while others may be found in the periodical "Animal Soul."[3] [2] Published by the committee through the agency of Professor Ziegler. [3] Published by Emil Eisell, in Bonn. Rolf has made frequent public appearances and been subjected to tests of several hours' duration. These have taken place both in the presence of his kind and gifted mistress and teacher, and also quite alone with his examiners. On every occasion of his appearance notes have been taken as to the procedures, and on one occasion these were even attested by a Notary. At such times, indeed, suggestions were not infrequently made which might be said to exceed every justifiable limit; tests were carried out prior to which the whole family had to vacate the house--carpets were taken up, in order to hunt for electric wires; window-shutters were closed; cupboards and premises searched, and sentinels posted--all this being tolerated by them with the utmost good-humour! And in spite of all this upheaval, Rolf was almost without exception ready with his replies! A fact that may well be set to his credit, when we consider how sensitive and capricious animals are by nature. Of his examiners, it may be said, that they covered themselves with confusion. One public appearance brought him well-merited praise from a large circle of acquaintances. So excellently did he acquit himself on this occasion that I should like to place it on record. "REPORT OF THE PUBLIC APPEARANCE OF THE SPELLING DOG ROLF "_By Professor H. F. Ziegler_