not seen" as in the case of the tests with the smaller
blinders. If we were to count the cases which we had put under the head
of "undecided," in the same category as those in which vision had been
excluded--as Mr. von Osten had done--then one would have been led to the
conclusion that the horse did not need visual signs. Several observers
had thus been led astray: e. g., General Zobel writes in the
"National-Zeitung" (Aug. 28, 1904), that upon request Mr. von Osten had
covered Hans's right eye "by means of some sort of blinder, so that he
was unable to see his instructor", and that Hans did not fail to respond
correctly. We evidently have here to do with the unreliable bolster
mentioned above. Furthermore, Mr. Schillings made a number of tests with
the small blinders, in which 50% of the answers were correct, and
probably in the same manner were obtained the results published in one
of the daily papers (the "Berliner Tageblatt", Dec. 12, 1904), several
days after the publication of the December report, and reading as
follows: "Tests have been made upon Hans with blinders over his eyes and
it is to be noted that, in spite of these, he still responds correctly."
Mention is also made of the experiments noted in Supplement III (page
257), in which Mr. von Osten hid behind the questioner and merely
encouraged the animal by occasional exhortations, but it is not possible
to say with any degree of certainty in how far he was really hidden from
the horse's view.

I would add that the horse--in so far as it was at all possible to
decide--never looked at the persons or the objects which he was to
count, or at the words which he was to read, yet he nevertheless gave
the proper responses. But he would always make the most strenuous
efforts to see the questioner. (See page 43). I would furthermore add
that several experiments, in which Mr. von Osten and the horse were
separated from each other by means of the canvas tent, failed
completely, and that, on the other hand, all tests were successful in
which the questioner was present in the feed-room and the door between
this and the horse's stall was opened wide enough for him to be seen by
the horse. I would also mention that toward evening the responses became
less and less accurate. The conclusion that visual stimuli were here
operative cannot be gainsaid.

It was possible, to be sure, that other senses might also be involved,
but it was certain that auditory sensations did not en