hunger in the redoubt at Magdebourg, saw himself in his dreams surrounded by sumptuous meals; and George Back, who took part in Franklin’s first expedition, when on the point of dying of hunger owing to their terrible privations, dreamt regularly of abundant food to eat.” Anyone who has made himself thirsty at night by eating highly-seasoned dishes at supper is likely to dream of drinking. Of course it is not possible to relieve acute hunger or thirst by dreaming; in that case we awake thirsty and are obliged to drink real water. The service of the dream is here of little practical account, but it is none the less clear that it was called up for the purpose of protecting sleep from the stimulus impelling us to wake up and act. Where the intensity of the desire is less, ‘satisfaction’-dreams do often answer the purpose. In the same way, when the stimulus is that of sexual desire the dream provides satisfaction, but of a kind which shows peculiarities worthy of mention. Since it is a characteristic of the sexual impulse that it is a degree less dependent on its object than are hunger and thirst, the satisfaction in a pollution-dream can be real; and, in consequence of certain difficulties in the relation to the object (which will be discussed later), it particularly often happens that the real satisfaction is yet connected with a vague or distorted dream-content. This peculiarity of pollution-dreams makes them, as O. Rank has observed, suitable objects for the study of dream-distortion. Moreover, with adults, dreams of desire usually contain besides the satisfaction something else, springing from a purely mental source and requiring interpretation if it is to be understood. We do not maintain, by the way, that wish-fulfilment dreams of the infantile type occur in adults solely as reactions to the imperative desires I have mentioned. We are equally familiar with short clear dreams of this type, occasioned by certain dominating situations and unquestionably produced by mental stimuli. For example, there are ‘impatience’-dreams in which someone making preparations for a journey, for a theatrical performance in which he is specially interested, or for a lecture or a visit, has his expectations prematurely realized in a dream, and finds himself the night before the actual experience already at his journey’s end, at the theatre, or talking to the friend he is going to visit. Or again, there is the ‘comfort’-dream, rightly so-called, in which someone who wants to go on sleeping dreams that he has already got up, that he is washing, or is at school, while all the time he is really continuing his sleep, meaning that he would rather dream of getting up than do so in reality. In these dreams the desire for sleep, which we have recognized as regularly participating in dream-formation, expresses itself plainly and appears as their actual originator. The need for sleep ranks itself quite rightly with the other great physical needs.