Thunder House
 THUNDER HOUSE: This ingenious article is made of an upright piece of baked mahogany, formed like the gable of a house... A wire runs downwards through its entire length. It is terminated above by a ball, which being unscrewed, shows a point beneath it. In one or two parts of the gable are square pieces of wood cut out. These are ¼ of an inch thick and 1 inch square on the side. They ... are made so as to fit loosely into a hole cut partly into the gable to receive them, and have a wire running across each, so placed, that putting in the pieces one way, the wires ... form a continuous and uninterrupted line, and when put in crosswise, there shall be a want of contiguity at that place.
   Pass the shock from [the top to the bottom of the wire] while the ball remains on, and the wire is continuous, and it will make a loud report, without
disturbing either piece of wood.
   Pass a shock, or rather endeavour to do so, with the upper ball taken off, so that the point is displayed. The fluid will pass and discharge the [Leiden] jar, but not in the manner of the shock, and no report will be heard.
   Now place either of the pieces of wood crosswise, and restore the ball to the top. The shock will pass and throw out the piece of wood that was placed crosswise, but not disturb the other piece.
   Let the piece of wood be placed crosswise, as in the last experiment, but remove the ball. Upon discharging the Leyden jar, a real shock will pass, and the wood will be displaced, although a point terminates the apparatus.
   FROM: George W. Francis, Electrical Experiments, eighth edition (J. Allen, London, 1855), pg 87

   The thunder house at the left below is at the apparatus collection at Transylvania University in Lexington, Kentucky. It is missing the lightning rod wire. At the right is the thunder house in the Harvard University Collection. Both of these wooden houses are designed to blow apart from the lightning strike from a Leiden jar.

   The tin house below is in the Transylvania collection. An identical Thunder House is in the Cabinet of Physics at Uppsala University in Sweden, and that one was obtained from Paris on or before 1840. The house will fall apart when the powder bomb inside is exploded by the electric shock.

   This thunder house, in the Millington/Barnard Collection at the University of Mississippi Museum, combines both forms of operation. The left-hand wall contains the square cutout in which the small piece of wood with the transversely-placed wire can be blown out. If the block is oriented so that there is a continuous conductor for the spark, a powder bomb inside can be ignited, and the hinged side of the house will blow open. 

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