These questions had all referred to the alternation of _two_ units; either a unit with an empty space, or with a space of different filling. How did the apperception differ when _three_ repeated units alternated with each other? To test this, three spaces were taken equally wide (110 mm.) and equally distant from each other (150 mm.), but with three different designs within them. These designs were of the same general character and importance although different, and repeated themselves regularly. [Illustration: Fig. 21] The subjects were asked as before to describe their reaction on the series. Not one of all the number was able to _feel_ the repetition of the three units; what pleasure they got from the series (if indeed they got any) was from other sources. The general type of answer was formulated more fully by L. He saw 1, then looked for 2 and found it different, but could have included it in the series if it were not for 3. That being still different sent 1 and 2 out of mind, so that he could not _feel_ any repetition of 1 when he met it again. He felt a certain sense of repetition in that the spacing and general motifs were the same, but there was no pleasure in that. What pleasure he got was wholly intellectual, not immediate, except for a slight pleasure in their uniformity of position. In him the rhythmic feeling had always been of the strongest, but he found in this experience none whatever. It was simply impossible to keep the three units going at once. Another temporal subject tried to group 2 and 3 as one element, with one as an alternate, thus reducing it to a rhythm of twos. This process was labored, but otherwise no enjoyment was possible. The spatial subjects derived what pleasure they could, either from the units separately, with no regard to their repetition, or from some method of grouping, by which their difference could be overlooked. One expressed his pleasure solely in terms of contrast of the white strings against a black ground. Any immediate feeling for the repetition was impossible for either type. It will be noticed that the _feeling_ of the repetition is quite different from the _knowing_ it is there. They were all perfectly conscious that 1 was repeated again after 3, but could not _feel_ it, while repeated simply after 2, they _could_ feel it. Next, the series was varied again. The size of the blocks, instead of being alike, was varied three ways, while the designs remained similar. [Illustration: Fig. 22]