To come back then to our horses and to the main point, which is the isolated "psychic flash," it is admitted that they know the values of figures, that they can distinguish and identify smells, colours, forms, objects and even graphic reproductions of those objects. They also understand a large number of words, including some of which they were, never taught the meaning, but which they picked up as they went along by hearing them spoken around them. They have learnt, with the assistance of an exceedingly complicated alphabet, to reproduce the words, thanks to which they manage to convey impressions, sensations, wishes, associations of ideas, observations and even spontaneous reflections. It has been held that all this implies real acts of intelligence. It is, in fact, often very difficult to decide exactly how far it is intelligence and how far memory, instinct, imitative genius, obedience or mechanical impulse, the effects of training, or happy coincidences. There are cases, however, which admit of little or no hesitation. I give a few. One day Krall and his collaborator, Dr. Scholler, thought that they would try and teach Mohammed to express himself in speech. The horse, a docile and eager pupil, made touching and fruitless efforts to reproduce human sounds. Suddenly, he stopped and, in his strange phonetic spelling, declared, by striking his foot on the spring-board: "Ig hb kein gud Sdim. I have not a good voice." Observing that he did not open his mouth, they strove to make him understand, by the example of a dog, with pictures, and so on, that, in order to speak, it is necessary to separate the jaws. They next asked him: "What must you do to speak?" He replied, by striking with his foot: "Open mouth." "Why don't you open yours?" "Weil kan nigd: because I can't." A few days after, Zarif was asked how he talks to Mohammed. "Mit Munt: with mouth." "Why don't you tell me that with your mouth?" "Weil ig kein Stim hbe: because I have no voice." Does not this answer, as Krall remarks, allow us to suppose that he has other means than speech of conversing with his stable-companion? In the course of another lesson, Mohammed was shown the portrait of a young girl whom he did not know. "What's that?" asked his master. "Metgen: a girl?" On the black-board: "Why is it a girl?" "Weil lang Hr hd: because she has long hair." "And what has she not?" "Moustache." They next produced the likeness of man with no moustache. "What's this?" "Why is it a man?" "Weil kurz Hr hd: because he has short hair."