Page:Popular Science Monthly Volume 47.djvu/442
THE POPULAR SCIENCE MONTHLY.
difference of potential he obtained between the earth and an insulated burning match placed nine feet above the ground was from two hundred to four thousand volts. What, then, is the result of permanently connecting by a good conductor the earth and the atmosphere directly above it, a condition that exists in the case of single-wire circuits? Such an arrangement must tend to equalize potential and prevent the accumulation of those charged masses which no doubt form the nucleus of the storm cloud. This equalization will continue to take place in all conditions of weather. But when a storm occurs it is obvious that if struck by lightning the wire carries the current to the point of greatest range — viz., to the instrument and to any one in its vicinity. Therefore, unless the strictest structural precautions be taken, such a wire becomes a source of danger rather than of safety. To obviate this danger, every post or support for overhead wires ought to be fitted with a lightning guard, and every instrument, whether using the earth as a return or not, should be furnished with a lightning arrester.
Conditions of Sleep. — Some interesting experiments on sleep have been made by Prof. I. Tarchanoff, of St. Petersburg, upon puppies from three weeks to three months old. The animals at this age have a strong disposition to sleep, and are not awakened even when physiological experiments are made upon them — a few minutes' stroking of the head and back assuring the persistence of their slumbers or their return to sleep if they are aroused. Adult dogs will not sleep under such circumstances, except with the aid of a narcotic. Position of the body exerts a distinct influence on the sleeping. Puppies lightly strapped were placed, some in a horizontal and others in a vertical position, and of the latter some were held with the head downward and others with the tail down. Stroking and caressing failed to induce sleep only when the head was kept down. Other experiments demonstrated that the arterial pressure falls during sleep, and that when the animal wakes it returns to its former height. These facts agree with the statements and observations of Mr. Darben that the brain is anaemic during sleep. Further experiments were made by Prof. Tarchanoff on animals in which the spinal cord had been divided between the dorsal and lumbar regions, and the animals had recovered from the immediate effects of the injury. The result was expressed in the observation that the spinal cord never sleeps. The author thinks, further, that the brain is not during sleep inactive in all its parts, but is a source of depressed action propagating itself to all parts of the cord which are in perfect continuity with the brain.
Physiological Influence of Music. — In the investigation of the influence of music on man and animals, Prof. Tarchanoff, of St. Petersburg, used the ergograph of Mosso, and found that, if the fingers were completely fatigued, music had the power of making the fatigue disappear. It appeared that music of a sad and lugubrious character had the opposite effect, and could check or inhibit the contractions. The author is inclined to suppose that the voluntary muscles, being furnished with excito-motor and depressant fibers, act in reference to the music similarly to the heart that is, that joyful music resounds along the excito-motor fibers and sad music along the depressant or inhibitory fibers. Experiments on dogs showed that music was capable of increasing the elimination of carbonic acid by 16·7 per cent, and of increasing the consumption of oxygen by 20·1 per cent. It was also found that music increases the functional activity of the skin. The author claims as the result of his experiments that music may fairly be regarded as a serious therapeutic agent, and that it exercises a genuine and considerable influence over the functions of the body.
A timely protest is made in the Pharmaceutische Rundschau against the proposition of some pharmaceutical schools to confer the degree of Doctor of Pharmacy. A forcible objection to the use of the term doctor in this connection was uttered in 18*74 by the Board of the Philadelphia College of Pharmacy, which deprecated the use of that title because the practices of pharmacy and medicine were so closely connected with each other that it would tend to confusion. A dispensing druggist possessing it would be supposed to have the right to prescribe, and danger of conflict