The thunder house is a scientific model invented by

James Lind James Lind (4 October 1716 – 13 July 1794) was a Scottish doctor. He was a pioneer of naval hygiene in the Royal Navy. By conducting one of the first ever clinical trials, he developed the theory that citrus fruits cured scurvy. Lind ...

which gives a spectacular demonstration of the destructive effect of a

lightning Lightning is a naturally occurring electrostatic discharge during which two electrically charged regions, both in the atmosphere or with one on the ground, temporarily neutralize themselves, causing the instantaneous release of an avera ...

bolt striking a house with an imperfect

lightning conductor A lightning rod or lightning conductor (British English) is a metal rod mounted on a structure and intended to protect the structure from a lightning strike. If lightning hits the structure, it will preferentially strike the rod and be conducte ...

. The small wooden house has hinged walls and carries a brass rod representing a lightning rod. A section of the conductor runs along a piece of wood placed on the façade. Inside the house is a spark gap housed in a small brass cylinder containing a small quantity of

gunpowder Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate (saltpeter). Th ...

. When the piece of wood is removed, the lightning-conductor circuit is broken. The lightning bolt, simulated by a spark generated by a

Leyden jar A Leyden jar (or Leiden jar, or archaically, sometimes Kleistian jar) is an electrical component that stores a high-voltage electric charge (from an external source) between electrical conductors on the inside and outside of a glass jar. It typ ...

, ignites the powder, whose explosion causes the house to collapse. If, instead, the piece of wood is positioned correctly, the electricity will be discharged to the ground, leaving the house intact. Filippo Lucci depicted a similar device in the Stanzino of the Matematiche of the

Uffizi Gallery The Uffizi Gallery (; it, Galleria degli Uffizi, italic=no, ) is a prominent art museum located adjacent to the Piazza della Signoria in the Historic Centre of Florence in the region of Tuscany, Italy. One of the most important Italian museums ...

in 1780—clear evidence of the popularity of such demonstrations in the late eighteenth century. The same phenomenon is also visible through the use of a similar instrument called ''Thunder Obelisk''.

Notes

Bibliography

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External links

* {{Cite web, url=http://catalogo.museogalileo.it/oggetto/CasaFulmine.html, title=Museo Galileo - object description, last=, first=, date=, website=, publisher=, access-date= Electrical safety Science demonstrations