Thunderbolts.

New Zealand Graphic, Volume XLVIII, Issue 17, 23 October 1912, Page 10

Thunderbolts.

The term thunderbolt is generally applied both to the rare phenomenon or ball lightning and to meteoric stones. In the latter ease its only meaning is that their luminous path resembles lightning, or that they cause great atmospheric disturbance. Here the term is applied only to ball lightning. The singularity of ball lightning consists in the complete isolation of a gaseous sphere having no en'velope, yet within which there is energy stored by previous electrical action; which, in the end. is liberated with explosive violence. From the few records of its appearance these facts (writes \V. M. Thornton, in the “Philosophical Magazine’’) may be considered as established. It is observed as a luminous blue ball occurring in very tense lightning Hashes, either falling slowly from clouds, or moving horizontally some feet above the earth’s surface. It is more frequently seen at -sea than on land. It appears to move under the action of gravitation on ft mass somewhat denser than air, or horizontally in a feeble air-current or an electric, field of force. The final features are significant. The ball ceases to exist, and an explosion wave travels outwards from the locus it occupied. In alt eases a strong smell of ozone follows its disappearance. It is clear there can be nothing present in it but the gases of the atmosphere.