If protection is desired, however, it is fully proved that a great quantity of scattered metal points — whether iron or copper is immaterial, and iron is cheaper is the most effective; a mesh of barbed-wire fence over the roof and chimneys would be not only the cheapest, but one of the most effective protections. The great steel buildings in New York City have all been struck time and again by lightning with out damage. The numerous metal points and corners draw the electricity and it is promptly absorbed and distributed through the massive steel framework. Perfect safety is thus ob tained by enclosing the building in a metal sheath, as no electric discharge can penetrate into an enclosed metal safe. The consensus of expert opinion now is that if a building is to be protected at all, numerous light iron rods are best, supported at a little distance from the structure and with numerous points. The old ((conduits theory of draining off the lightning and having a good conductor to prevent re sistance and insulators to prevent jumping is now discarded: it is recognized that there is an enormous amount of electric energy to be dis charged almost instantly, it is almost certain to distribute itself around a considerable area and all that the points can do is to ensure and regu late that distribution. If lightning-rods are used there should always be a good •grounds or °earths at the bottom, as a ton of coke or a water ditch. The last statistics on lightning damage gathered and published by the United States Weather Bureau was in 1900, giving
ures for the previous year, as nearly as they could be obtained. A total of 5,527 °strikes' were recorded, injuring 6,256 buildings. The property loss was a little over $3,000,000 and 4,251 head of livestock were killed, of a value of $130,000. Most of this latter was due to cattle contacting barbed wire fences in thunder storms. Consult Lodge's
About five or six persons per million die annually from lightning-shocks. The effects of lightning stroke on the body are similar to those pro duced by large amounts of electricity at high voltage. Persons subjected to the influence of lightning-stroke may suffer very slightly or may be killed, and between these extremes a vast variety of minor or major injuries may result. The most characteristic form of injury is some sort of burn. This occasionally shows on the skin as an arborescence, which was formerly thought to resemble the tree under which a patient had sought shelter during a storm, but is, of course, solely an effect of the zigzagging of the electrical discharge. In many persons
mental shock and prolonged nervousness are frequent symptoms. Mild stunning, with a sense of suffocation, may be experienced when an electrical bolt strikes near a person, and oc casionally nervous and hysterical attacks are in duced. Suppression of menstruation and abortion have been reported. Numbness and prickling of various areas of the body; Paraly sis of the muscles; deafness; loss of smell and taste; and paralysis of the bladder and rectum have all been described. Occasionally insanitY has followed lightning-stroke. Other experi ences of persons who have been exposed irr dude flashing in the eyes, buzzing in the ears, general tremor, which may go on to convulsions, with or without loss of consciousness, and peo ple who have been seen in this stage have been described as being blue, with muscles tightly contracted, the pupils dilated, the breath deep and snoring and pulse feeble. Since there are more than 30 deaths by suicide to one by light ning-stroke, it would seem wholly unnecessary for the average individual to worry over the likelihood of his earthly career being ended by lightning.
In death by lightning, changes in the nerv ous system have been found and it is probable that the cause of death may be either the re sult of minute hemorrhages, which take place in the important centres of breathing and of the heart-action and in the medulla; or death may be the physiological effect of the electric ity on the heart, causing a form of heart-tet anus, with rapid cessation of the movement of this organ.
The treatment of lightning-stroke, as well as of other forms of electrical injuries, should be promptly instituted. If commercial currents are the cause they should be removed at once, care being taken to use insulating materials to remove live wires. External heat to the body with hot-water bottle, cardiac stimulation with whisky, ammonia, etc., with artificial respira tion, should be simultaneously used.
No method of artificial respiration or other attempt to produce consciousness should be abandoned under three to six hours, as often no signs of life may be brought out in less than two to three hours. It is seriously advised by some observers that, before giving up all hope, an injection of an alkaline solution into the blood should be used. Hot saline solution may be thrown into the rectum and the treatment should be continued until all possible methods of resuscitation have been employed. Consult Jelliffe, 'Death by Lightning and Electricity' (in 'Text-book of Legal Medicine and Toxi cology,' 1903) ; 'Death by Electric Currents and by Lightning' (in British Medical Journal, London 1913).