SCIENCE OF THE DAY.

New Zealand Herald, Volume LXV, Issue 19838, 7 January 1928, Page 5 (Supplement)

SCIENCE OF THE DAY.

TESTS REGARDING SLEEP. Sleeping on behalf of science, 12 men of tlio Mellon institute at Pittsburg, United States, says a recent despatch, doze away the hours while delicately adjusted instruments automatically record the soundness or fitfulness of their slumber. They are the only persons in the world, so far as is known, who are paid < to sleep. These 12 men are the subjects under scientific observation in t!.o Industrial Fellowship for the Investigation of tho Physiological and Hygienic Aspects j of Sleep. The fellowship was founded at -the institute last year by a prominent manufacturer of beds and bedding equipment and its purpose is declared to be strictly non-commercial. It was the desire of the bedding manufacturer primarily to ascertain in what ways and to what extent the quantity and distribution of rest affect the welfare of the individual, and to ascertain in what ways this end might bo furthered by selection and improvement of product. Dr. H. M. Johnston, assistant professor of psychology at Ohio University,who was in charge of the tests, said:— "To go to sleep you must relax. You cannot relax while you think or think while you relax. So you need to practice relaxation until you make it a matter of habit. If you cannot train yourself to relax find a regular physician to help you learn. Do not go in for new thought stuff or mental healing or other fads of the kind. I urge this upon you, for thi3 sort of training is somewhat- akin to self-hypnosis and you do not want to cultivate an attitude of suggestibility which will extend to other institutions." The Mellon Institute sleepers, in the time that they were engaged in their unconscious task, developed a code of ethics strictly professional. They declared that they had no interest in the tests and exEeriments, being mere automatons in the ands of the scientists.

THE MANNA MYSTERY. The nature of the Biblical manna is thought to have been established by an expedition which recently return from Central Sinai. The traditional theory was that the Biblical manna was identifiable with the tamarix mannifera, a species of the tamarix shrub which exudes a sugary secretion called manna. It was thought that manna wjis a natural

secretion from the twigs or buds which were pierced by rodent insects. The expedition has determined that manna is an excretion of the insects themselves;, which produce clear syrup-like drops that, if sufficiently abundant, fall to the ground, forming whitish grains from the size of a pin's head to the size of a pea. The quantity of this secretion depends on the rain, but in a good season a man can collect about 31b. in a day. POISON FOE RATS. Interesting experiments for showing the efficacy of red squill poison for destroying rats and mice are described m the British Journal of the Ministry of Agriculture. Red squill is advocated in preference to stronger poisons like strychnine, arsenic, and phosphorous on farms and spots where there are poultry, live stock, or stored food. Recent experiments disclosed that femaJe rats are killed by an average dose of .27 grammes, compared with .50 for male rats. _ Calves, sheep, pigs and rabbits Rere given red squill powder in their feed, and though they had been given no other food in the preceeding 24 hours, it was found almost impossible to induce the animals to eat any appreciable quantity of the poisoned feed. Fowls took , the poison more readily, but in their case a fatal dose was 20 to 30 times as largo as that necessary to kill a rat. The experiments appeared to show that, while fatal to rats, red squill poison is comparatively harmless to larger animals.