Lightning Conductors: Their History, Nature, and Mode of Application

by F.C.S. Richard Anderson

Thomas Fuller, in his ‘Church History of Britain,’ states that—

‘There was scarce a great abbey in England which (once, at the least) was not burnt down with lightning from Heaven. 1. The Monastery of Canterbury, burnt anno 1145, and afterwards again burnt anno 1174. 2. The abbey of Croyland, twice burnt. 3. The Abbey of Peterboro, twice set on fire. 4. The Abbey of Mary’s in York, burnt. 5. The Abbey of Norwich, burnt. 6. The Abbey of St. Edmondsbury, burnt and destroyed. 7. The Abbey of Worcester, burnt. 8. The Abbey of Gloucester. 9. The Abbey of Chichester, burnt. 10. The Abbey of Glastonbury, burnt. 11. The Abbey of St. Mary in Southwark, burnt. 12. The Church of the Abbey of Beverley, burnt. 13. The steeple of the Abbey of Evesham, burnt.’

Even in those cases where in modern times lightning conductors have been applied to buildings, they are very often improperly fixed in the first instance, or, having once been put up, are never examined or tested with the view of ascertaining their constant efficiency. Several accidents owing their origin to one or the other of these causes have occurred quite recently. In May 1879, the church at Laughton-en-le-Morthen was struck by lightning and damaged in the manner described in Chapter XIII. The spire was fitted with a corrugated copper tube conductor the joints of which were made by screws and coupling-pieces, but there was no metallic contact between the lengths; the conductor was insulated from the building; and the earth-contact was obtained by bending the end of the tubing, and inserting it about twelve inches deep in dry loose rubbish! Such a conductor is worse than useless. If it had been examined by a competent person, it must at once have been utterly condemned. In June 1879, a disastrous result followed the use of a similar conductor erected upon a private house near Sheffield. In this case the corrugated tube forming the conductor contained too little metal, and it was insulated from the building. The examples show the necessity of leaving the design and erection of lightning conductors to those persons who have made a thorough study of the subject, since the work is by no means so free from complexity as is commonly supposed.

Fig. 40. ST. GEORGE’S CHURCH, LEICESTER.

[Figs. 40] and [41] show the tower and spire of St. George’s Church, Leicester, after being severely damaged by lightning on August 1st, 1846. The storm, during the course of which it was struck, was very violent, of prolonged duration, and accompanied by torrents of rain and hail. Mr. Charles Tomlinson, F.R.S., in his work on ‘The Thunderstorm,’ thus describes the catastrophe:—

‘It was at five minutes past eight, after one or two peals of unusual distinctness, that the church of St. George was struck with a report resembling the discharge of cannon, and with a concussion of the air which shook the neighbouring houses, and extinguished a lamp burning at the entrance of the News-room, many hundred feet distant. The Sexton had gone into the church, as usual, to toll the eight o’clock bell; but was so terrified by the “fire-balls” that he saw in the sky, and by the fact that once or twice the clapper struck the side of the bell without his agency, that he made his work as short as possible, and had just gone out and locked the churchyard gate when the stroke fell. Two of the spectators of this awful event were Captain Jackson and the Rev. R. Burnaby, the rector of the parish, who both described the flash as a vivid stream of light, followed by a red and globular mass of fire, and darting obliquely from the north-west, with immense velocity, against the upper part of the spire. For the distance of forty feet on the eastern side, and nearly seventy on the west, the massive stone-work of the spire was instantly rent asunder and laid in ruins. Large blocks of stone were hurled in all directions, broken into small fragments, and in some cases, as there is every reason to believe, reduced to powder. One fragment of considerable size was hurled against the window of a house three hundred feet distant, shattering to pieces the woodwork, as well as fourteen out of the sixteen panes of glass, and strewing the room within with fine dust and fragments of glass. It has been computed that a hundred tons of stone were on this occasion blown to a distance of thirty feet in three seconds. In addition to the shivering of the spire, the pinnacles at the angles of the tower were all more or less damaged, the flying buttresses cracked through and violently shaken, many of the open battlements at the base of the spire knocked away, the roof of the church completely riddled, the roofs of the side-entrances destroyed, and the stone staircases of the gallery shattered. The top of the spire, when left without support beneath, fell perpendicularly downwards, inside the steeple, causing much devastation in its descent. Falling through the uppermost storey, and carrying along with it the bell and its solid supports, the ruined spire entered the room containing the clock, dashed the works to pieces, and penetrating the strong and well-supported floor, descended with additional momentum through the third and fourth floors (the latter being that just deserted by the prudent sexton), and reached the paved vestibule with so furious a shock as to drive in a portion of the strong foundation-arch, by which the weight of the whole tower was supported. On looking upward from the scene of ruin in this vestibule, the tower appeared like a well, so small were the vestiges of its various storeys.’

Fig. 41. ST. GEORGE’S CHURCH, LEICESTER.

After minute examination, it was evident that the course of the lightning had been nearly as follows:—‘The flash first struck the gilded vane, marks of lightning being perceptible between its bevelled edges. After traversing the vane and spindle, and the terminating iron supports, the only path left for the fluid was through a series of iron cramps, separated by masses of sandstone; and here it was that the explosion commenced—the stone being torn and hurled aside as it came in the path of the lightning to the lowest lead lights of the spire. Most of these iron cramps were found to be powerfully magnetic; and one of them, eight weeks afterwards, sustained a very considerable brush of steel filings at its edges. The lattices of the lights on three sides of the spire were little injured; but on the fourth side the stone-work was shattered, and the lattice singularly twisted and partially fused. Here, it appears, another violent explosion took place, and the lightning diverging struck the north-west pinnacle, attracted apparently by the copper bolt by which the stones were held together. It also struck the large cast-iron pipe on the other side of the spire, reaching from the tower-battlements to the roof of the church; and during its passage down the pipe, and at an inequality in the surface of the metal, it displayed the most extraordinary expansive force, bursting open and scattering to a distance portions of metal of great solidity and weight. From the leadwork of the roof the lightning was conducted to the leaden gutters, and so finally to the earth.