Cases of lightning discharge
G.E.V. Thomas, a civil engineer in the Straits Settlements, published this short communication in 1900, presenting a collection of observed lightning phenomena from Singapore and Penang that he argued demonstrated both the frequency and violence of thunderstorms in Malaya and the inadequacy of contemporary lightning protection systems. The article was communicated by H.N. Ridley, Director of Gardens and Forests, whose own field observations form a substantial portion of the evidence.
Summary
Thomas’s central contribution is the documentation of a previously unnoted after-effect of lightning strikes on trees: the progressive death of surrounding vegetation radiating outward from the struck specimen. Drawing on Ridley’s diary entry of 3 May 1898, he describes a coco-nut plantation at Siglap where eleven trees died in a semicircle around a single struck tree, their foliage appearing burnt and their decline occurring over weeks rather than instantaneously. A parallel case on Government Hill (2 May 1899) showed sugar palms within a twelve-to-fifteen-foot radius of a struck specimen completely dead three months later, despite no visible damage at the time of the strike. Thomas presents these as evidence that lightning’s effects extend well beyond the immediate point of impact, a finding he notes had not previously been recorded.
The article also assembles several accounts of globular or ball lightning, a phenomenon then considered dubious by the scientific community. A. Knight’s two observations from September and October 1898 describe a flame-coloured flash accompanied by a sulphurous smell and a sensation of electric shock, and a greenish-white explosion in the air four to five feet above the ground. Ridley’s own account of a ball of fire descending in a curve and exploding close to the ground, leaving no mark on the grass, is presented as corroborating evidence. Thomas explicitly notes that no photograph of the phenomenon had ever been obtained, a point he laments.
The final section turns to structural damage, focusing on two lighthouse cases that expose the failure of single-conductor lightning protection. At Cape Rachado, a side flash left a copper conductor at a bend and punched holes through solid masonry walls. At Muka Head (9 October 1897), a flash struck the conductor, tore off a gunmetal brace, then abandoned the heavy copper rod entirely to travel through a thin telephone earth wire, deflagrating thirty feet of it. Thomas uses these cases to argue that the prevailing assumption—that a sufficiently tall conductor with sharpened points and low earth resistance could protect a building of any size—was demonstrably false.
Key Findings
- In a Siglap coco-nut plantation, eleven trees died in a semicircle around a single struck tree, with the deaths radiating outward progressively over more than a month (p. 251).
- On Government Hill, sugar palms within a radius of twelve to fifteen feet of a struck specimen were completely dead three months after the strike of 2 May 1899, despite no visible damage at the time (p. 252).
- A. Knight observed a globular lightning event on 14 October 1898: a greenish-white explosion in the air four to five feet above the ground, confirmed by neighbours whose line of sight was at right angles to his (p. 253).
- At the Cape Rachado Lighthouse, a side flash left the copper conductor at a bend, made holes in solid masonry walls across two rooms, and was finally dissipated over a sheet of rainwater in a courtyard (p. 254).
- At Muka Head (9 October 1897), the discharge abandoned the heavy copper conductor and travelled through a thin telephone earth wire, completely deflagrating thirty feet of it (p. 255).
- A Signal Sergeant on Penang Hill reported that in April 1898 a telegraph pole was cut in half horizontally “as if it were sawed off,” with the wire cut in three or four places and three insulators broken (p. 255).
Conclusion
Thomas’s definitive takeaway is twofold: first, that lightning in the Straits Settlements produces a range of effects—progressive vegetative death, globular discharge, side flash, and conductor abandonment—that are underdocumented and poorly understood; and second, that the single-conductor protection system then standard in colonial infrastructure was unreliable and potentially dangerous, as it could channel destructive discharge through unintended paths. He closes by inviting further observations and photographs to build a more complete record of these phenomena.
Context
- Thomas held the qualification A.M.I.C.E. (Associate Member of the Institution of Civil Engineers) and was evidently employed in a technical capacity within the colonial administration; the article reflects the practical engineering concerns of the Straits Settlements government, particularly the vulnerability of lighthouse and telegraph infrastructure.
- The primary sources are field diaries, lighthouse keeper reports, and eyewitness accounts from colonial officials and residents, with no archival collection beyond these personal records. The article’s historiographical value lies in its early systematic documentation of lightning effects in a tropical setting, predating modern atmospheric physics research in the region.