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brought: IV IV III III I III V IV

The interpretation of this series which it would be hard to explain by a
reference to the colors which were mistaken, is simply this: Cloths
lying near together were regularly mistaken on the part of the horse.

Experimental control of the questioner's movements decided the question.
If the questioner at first indicated the proper direction and then
turned about after the horse had already started forward, he was as a
rule misled. When the questioner did not face the cloths at all, but
turned away at right angles, or when he turned his back upon them, Hans
was completely at sea. If, on the other hand, the cloths were arranged,
not in a row, but in several heaps, so that one might turn to a
particular heap, but could not indicate a particular cloth, then Hans
would regularly go to the proper heap, but would always bring forth the
wrong cloth. After much persuasion Mr. von Osten consented to make a
series of these tests himself. Hans's failures were deplorable. He would
take up first one cloth then another, turn again to the first, etc. We
would mention, however, that this apparent searching was not done
spontaneously, but in response to Mr. von Osten's calls, such as "See
there!", "The blue!", etc. Every time Mr. von Osten called, Hans would
drop the cloth he was holding in his mouth, or he would turn away from
the one he was about to grasp, and would then try another one.

In addition to these visual signs, the horse received auditory signals
in these tests, (as in all others in which he was required to bring
objects). As soon as the questioner noticed that Hans was about to take
up the wrong cloth, all that was necessary to make him correct his error
was to give some sort of an exclamation, such as "Wrong!", "Look, you!",
"Blue!", etc. Hans would pass on as long as the calling continued. If
he was picking up, or about to pick up, a cloth when the exclamation was
made, he would go on to the next; but if, at the time he was on his way
to a certain cloth, he would change his direction in response to the
call. If he stood before one of the pieces at the time, but had not
lowered his head, he would pass on to the next. In all this he would
adhere to a certain routine of procedure. If he was approaching a series
from the right, then a call would cause him to turn to the left, if he
was coming from the left, he would turn to the ri