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of muscle relaxation and so on, can be achieved by a brief period lying, or even sitting down. The body's
tissues
are
self-repairing
and
self-restoring to a degree, and function best when more or less continuously active. In fact a basic amount of movement occurs during sleep which is specifically concerned with preventing muscle inactivity.
If it is not a question of resting the body, then perhaps it is the brain that needs resting? This might be a plausible hypothesis were it not for two factors. First the electroencephalograph (which is simply a device for recording the electrical activity of the brain by attaching electrodes to the scalp) shows that while there is a change in the pattern of activity during sleep, there is no evidence that the total amount of activity is any less. The second factor is more interesting and more fundamental. In l960 an American psychiatrist named William Dement published experiments dealing with the recording of eye-movements during sleep. He showed that the
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average individual's sleep cycle is punctuated with peculiar bursts of eye-movements, some drifting and slow, others jerky and rapid. People woken during these periods of eye-movements generally reported that they had been dreaming. When woken at other times they reported no dreams. If one group of people were disturbed from their eye-movement sleep for several nights on end, and another group were disturbed for an equal period of time but when they were not exhibiting eye-movements, the first group began to show some personality disorders while the others seemed more or less unaffected. The implications of all this were that it was not the disturbance of sleep that mattered, but the disturbance of dreaming. Lesson24
Walking for walking' s sake may be as highly laudable and exemplary a thing as it is held to be by those who practise it. My objection to it is that it stops the brain. Many a man has professed to me
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that his brain never works so well as when he is swinging along the high road or over hill and dale This boast is not confirmed by my memory of anybody who on a Sunday morning has forced me to partake of his adventure. Experience teaches me that whatever a fellow-guest may have of power to instruct or to amuse when he is sitting in a chair, or standing on a hearth-rug, quickly leaves him when he takes one out for a walk. The ideas that come so thick and fast to him in any room, where are they now ? where that encyclopaedic knowledge which he bore so lightly ? where the kindling fancy that played like summer lightning over any topic that was started ? The man's face that was so mobile is set now; gone is the light from his fine eyes. He says that A (our host) is a thoroughly good fellow. Fifty yards further on, he adds that A is one of the best fellows he has ever met. We tramp another furlong or so and he says that Mrs A is a charming woman. Presently he adds that she is one of the most
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charming women he has ever known. We pass an inn. He reads
vapidly aloud to me: 'The King's Arms. Licensed to sell Ales and Spirits.' I foresee that during the rest of the walk he will read aloud any inscription that occurs. We pass a milestone. He points at it with his stick, and says' Uxminster. II Miles.' We turn a sharp corner at the foot of the hill. He points at the wall, and says' Drive Slowly.' .I see far ahead, on the other side of the hedge bordering the high road, a small notice-board. He sees it too. He keeps his eye on it. And in due course. 'Trespassers,' he says, 'will be Prosecuted.' Poor man !—mentally a wreck. Lesson25
How it came about that snakes manufactured poison is a mystery. Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today. It was not forced upon them by the survival competition; they could have caught and lived on
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prey without using poison just as the thousands of non-poisonous snakes still do. Poison to a snake is merely a luxury; it enables it to get its food with very little effort, no more effort than one bite. And why only snakes ? Cats, for instance, would be greatly helped; no running rights with large, fierce rats or tussles with grown rabbits- just a bite and no more effort needed. In fact it would be an assistance to all the carnivorae--though it would be a two-edged weapon -When they fought each other. But, of the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders also why Nature, with some snakes concocted poison of such extreme potency. In the conversion of saliva into poison one might suppose that a fixed process took place. It did not; some snakes manufactured a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects. One poison acts on the nerves, the other on the blood.
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