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Alexander George McAdie
(4 Aug 1863 - 1 Nov 1943)
American meteorologist who followed Benjamin Franklin in employing kites in the exploration of high altitude air conditions. He was second director of the Blue Hill Meteorological Observatory.
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NEEDLESS ALARM DURING THUNDER-STORMS.
BY ALEXANDER McADIE.
from Century Magazine (1900)
[p.604] The year 1753 is memorable in the history of electrical development. The experiments of the colonial philosopher with lightning had awakened a general enthusiasm in the scientific circles of Europe. In at least three capitals philosophers were pressing hard after Franklin, and great activity was shown, when suddenly there occurred in St. Petersburg a mishap which checked the ardor of all investigators, and exerted an influence which has lasted until to-day. During a thunder-storm, while stooping the better to follow the indications of an electrical “gnomon” (in modern phrase, electrometer), Richman met instant death. Coins in his pockets were fused, and many of the tearing and throwing effects associated with high potential, oscillatory discharges were apparent. Richman’s companion, standing three feet away, was uninjured, although much damage was done to the doors and woodwork of the room. This escape has been frequently commented upon, but a systematic study of the conditions determining immunity has never been made. The trend of investigation has been in the other direction, and the fatality of lightning has been perhaps unduly emphasized. Voltaire crystallized this [p.605] general view by caustically saying, apropos of Richman’s death: “There are some great lords whom it does not do to approach too closely, and lightning is one of these.” The opinion expressed by Voltaire is to some extent held even at the present day, and this, joined with the fact that no immediate practical use could be made of the electricity of the air, has hampered investigators, and retarded the advance of knowledge in this direction. Investigation must precede practical application, and if we would successfully harness the electricity of the air, we must first know something of its energy. Steadily, though slowly, this measuring process has been carried on.
Repeating, in a way, the experiments of Franklin and Richman, we attempted in 1887, from the top of the Washington Monument, then the highest edifice in the world, to measure the electrical potential of the air during a thunder-storm. Potential values of several thousand volts were indicated by the electrometer. The crackling and hissing of the sparks, with the attendant phenomena, were intensely exciting. With each flash there were marked electrical manifestations, but at no time did the experimenter consider himself to be in great danger. In 1891, at Blue Hill, during experiments in kite-flying in a thunder-storm, the wired kite-string was led into the observatory, connected with an electrometer, and an attempt made to secure a record of the variations in the potential. Here, again, the situation was seemingly critical. As the storm progressed, the electrical phenomena were so marked that we wished ourselves well out of the experiment. But beyond a rather severe shock, experienced while making some necessary connections, there were no harmful results.
Not for a moment do we underestimate the destructive power of lightning. No one should attempt experiments like those mentioned without taking every precaution; for positive danger lurks in the charged cloud, and, as in the handling of explosives, a small omission in details or an imprudence brings disaster. Yet the daily handling of currents far deadlier than ordinary lightning-flashes is a reassuring fact, and points to a coming mastery of the latter.
The keen suffering which many undergo just in advance of or during a thunder-storm is of a dual nature. The sense of impending danger alarms and terrifies; but there is also a depression of spirits which is physical and real, brought about by some as yet unknown relation between the nervous system and conditions of air-pressure, humidity, and purity. The suffering due to depression and partial exhaustion requires, from those who are strong, sympathy rather than ridicule. The suffering due to alarm and fright, however, is unnecessary. It is largely the work of the imagination. To a nervous nature there is something appalling in the wicked, spiteful gleam of the lightning, and the crash and tumult of thunder. But such a one should remember that the flash is almost always far distant, and that thunder can do no more damage than the low notes of a church organ. Counting all the deaths from all the storms during a year, we find that the chance of being killed by lightning is less than one in a hundred thousand. The risk in the city may be said to be five times less than in the country. Dwellers in city houses may be startled by peals of thunder, but owing to the great spread of tin roofing and fair ground connections, there is very little danger. In the country, if buildings are adequately protected, and the momentum of the flash provided for, the occupants may feel secure. A good conductor well grounded is necessary in all isolated and exposed buildings. Barns, especially when filled with green crops, should have good lightning-conductors. The question is often asked, “Do trees protect? “The answer is that the degree of protection will vary with the character of the tree and its distance from a watercourse. An oak is more liable to lightning-stroke than a beech. The character of the wood, the area of leafage, the extent and depth of root, will determine the liability to stroke. Another question which is often asked is whether there is danger aboard a large steamship during a thunder-storm. On the contrary - there are few safer places. Sufficient metal with proper superficial area is interposed in the path of the lightning, and its electrical energy converted into harmless heat and rapidly dissipated. Accidents occur chiefly because the victims ignorantly place themselves in the line of greatest strain, and thus form part of the path of discharge. For this reason, it is not wise to stand under trees, near flag-poles or masts, in doorways, on porches, close to fireplaces, or near barns. Those who are not exposed in any of these ways may feel reasonably safe. It should be remembered, in the event of accident, that lightning does not always kill. It more often results in suspended animation than in somatic death. Therefore, in case of accident, try to restore animation, keep the body warm, and send for a physician without delay.
- 4 Aug - short biography, births, deaths and events on date of McAdie's birth.
- Articles written by Alexander McAdie
- Theory and Practise of Frost Fighting - article by Alexander McAdie from Scientific Monthly (1915)
- The Storage Battery of the Air - article by Alexander McAdie from Harpers New Monthly Magazine (1894).
- What is an Aurora - article by Alexander McAdie from The Century Magazine (1897).
- Muir of the Mountains - Alexander McAdie writing about John Muir in Sierra Club Bulletin (Jan 1916).
- Franklin's Kite Experiment With Modern Apparatus - article by Alexander McAdie from Popular Science (1897).
- Making the Weather, by Alexander G. McAdie. - book suggestion.