THUNDER AND LIGHTNING.
IT does not happen often that we get in England so prolonged a series of thunderstorms as those of the early part of the past week. Monday in some parts of the country, and Tuesday in others, were days of practically continuous storms, with hardly an interval between the passing of one storm and the coming of another. A great deal of damage, naturally, is reported from many places. Chimney-stacks struck, the iron girders of buildings twisted into all kinds of shapes, the roofing ripped off a church, telephone-wires fused, switchboards set on fire, electric bells ringing all through a town, horses
and cattle killed in the field,—these are only a few of the incidents of the storm, which seems to have been heaviest in the northern parts of Sent, the Evesham district, and Salisbury Plain. A young girl in charge of two children, sheltering under a tree on Chislehurst Common, was struck by lightning and killed,—one of those dreadful instances of the sort of personal touch with which lightning seems to select its victim, for though one child is reported to have been thrown down, neither, apparently, was injured. There are many instances, of course, of this strange selection, due in most cases, probably, to some accident of clothing. There is a well-remembered case which happened some years ago at Cambridge, when three young men were walking across an open space of ground, and the middle one of the three was struck dead, while the others were untouched. The inquest showed that the young man who was killed had nails in his boots, whereas the others were wearing boating-shoes.
Not all the curious incidents of a great thunderstorm, of course, come to be reported. If a collection could be made of examples of the freakish way in which lightning behaves during a severe electric disturbance, it would make fascinating reading. An odd power which lightning appears to possess is that of hurling bodies from one place to another without otherwise damaging them. It seems to dealt a tremendous buffet, like an irresistible gust of wind. There have been numbers of instances reported this week of men thrown down on the ground, or hurled across a room, but not hurt in other ways. There was a case a year or two ago of an old man who was hurled out of his cottage door ; the lightning seemed to come in and throw him out, as it was described afterwards. The way of lightning with a tree is one of the strangest of all. A tree that has big struck is a familiar sight, though few have the good fortune to see the blow actually fall ; few, perhaps, who see it can tell others what they saw. Two years ago the writer asked an old labourer to describe what happened when a tall ash-tree in a field close by his cottage was struck. Apparently he was in his gaeden and saw the tree struck, but he could not say what happened. All that he knew was that there was a terrible noise; be never wanted to hear such a noise again, he said. Yet there must have been a good deal to see too. The tree was riven almost to the earth, so that you could see the sky through great gaps in it, and the bark was blown clean off the stem ; there were great shards and slices of bark lying twenty and thirty yards away from the bole all round the tree. Possibly what happens, in the case of a tree struck in this way, is that the heat of the lightning turns the sap of the tree into steam, and the steam suddenly generated between the wood and the bark blows the bark off like a boiler bursting.
The length of time during which the storms lasted on Monday and Tuesday must have made a large number of travellers familiar with the rather uncomfortable experience of being in the middle of a severe thunderstorm in a train. It was a curious sensation, travelling on the London and South- Western Railway on Tuesday, to find not only one, but two, and possibly three, separate storms going on at once down the line. On each side of the railway in the distance there were flashes of lightning followed by thunder after a con- siderable interval, while immediately above the train, just as if the storm were racing down the line with the engine, the lightning and the crash of thunder were simultaneous. Except under a corrugated-iron roof in a heavy hail- storm, there can be few noisier places than a railway carriage with thunderclaps crashing immediately above the chimney-pots. The lightning, too, has a rather dis- comfiting way of apparently darting straight through the carriage. With so much metal about the engine and the coaches, a train would seem to be naturally attractive to lightning ; but how many instances are there of a train being struck ? Perhaps the absence of metal pointing upwards Accounts for the immunity of railway rolling-stock. One of the most dangerous situations of any kind of travelling in a storm is that of troops marching along a road with rifles. There have been several remarkable experiences of this kind on Salisbury Plain ; and Wednesday's papers report a fearful lightning-flash in Germany, when the 177th Infantry Regiment, marching to camp at Kiinigsbriick, was struck, and out of two squads three men were killed and fifteen injured. The phenomena of thunderstorms have been the subject of much study in America. In afr interesting and comprehensive summary of recent work entitled "Descriptive Meteorology" (Appleton, 12s. 6d.), Dr. Willis Moore, Chief of the United States Weather Bureau, divides thunderstorms into three classes. First, tbere are sporadic thunderstorms, "apparently caused by special regions of warm air dotting the large areas of high pressure and clear sky." Second, there are storms that occur " in regions of southerly winds south-east or north-east of the central low,' caused probably by the deflection of these surface winds upward by hills or shore lines, or by their convergence toward the head of a bay, conditions that stimulate the formation of large cumulus clouds." Third are "those that occur south or south-west of the low center and are located on the front or advancing edge of an extensive mass of cooler or drier, and therefore denser air, which is slowly descending from the upper atmosphere and under- running or lifting up the warmer and moister air in front of it. These lattee," we are told, " are the most intense of all thunderstorms." But if thunderstorms can be classified, they are still not thoroughly understood. We do not yet know what are the exact conditions which lead to a discharge of electricity, in the form of a lightning-flash, from cloud to cloud or from cloud to earth. We cannot reproduce thunder and lightning in a laboratory. We do not know what is the origin of the electrification manifested in a storm. Dr. Willis Moore suggests that it is possible that among minor processes at work are irietion, the discharge of vapours from volcanoes, chemical activity and induction; but he believes that at present experiment is best directed, first, to the theory that the outer atmosphere of the earth is continually being bombarded or " ionised " (a word presumably derived from the Greek ion, an arrow) by electrified corpuscles or electrons issuing. Second, he recommends the theory that electric separation is produced by the breaking up of large raindrops into smaller ones by an up-rushing current of air. But, generally speaking, we must admit that we know very little about the whole process.
Except for the loss of life and damage to property, the storms we have just had will do a great deal of good. Rain was badly needed for crops and gardens. But in one respect the date of the storm was almost the unluckiest that could have been chosen in the year. The beginning of the second week in June is the date when, as a rule, young partridges are hatched out ; probably more broods are hatched during the period June 7th-12th than during the rest of the year. And, unfortunately, heavy rain is terribly destructive to the young birds. If the parents have time, they generally try to get their little chicks to the hedges or under cover when thunder- showers come on; but that is impossible, of course, with a nest in process of hatching, and in many places, in very large fields, for instance, or on exposed ground, there is no cover to which the birds can go in any case. The result is that the chicks are caught in the rain, or in flooded furrows and ditches, and drowned in hundreds. Whether this has actually happened as a consequence of the storm it is impossible at the time of writing to discover; it must be hoped that the low-lying ground has not come off so badly as it seemed likely it would. There is always a sense of extra misfortune when the partridges lose their broods, if only because the birds are such excellent parents. The cock is every whit as careful and trustworthy as the hen, and waits by the hen when the eggs are chipping, to take charge of and brood over each little chick as it leaves the egg.
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