FIGURE 15.Entrances to multiple-choice boxes as seen from the response-compartment.

The other important portions of the apparatus are the runway D, from which the subject at the experimenter's pleasure could be admitted through doorway 12 to the large response-chamber E; the alleyways G, H, and I, by way of which return to the starting point was possible; the observation bench C, with its approach step 13; and the observer's writing table A.

The structure of this hour is similar to that given in Terce above, the hymn, antiphon, psalms, little chapter and responses differing, but the order and form being similar in both.

instinct, brute instinct, stimulus-response loop, conditioned response, instinctive reaction, Pavlovian response.

The metallic voice of an automatic response system came on.