Electrical discharge mb-artist A_Heffer by Nehemiah Grew (London

by Nehemiah Grew (London

The villa has a greenhouse to one side

View of St Paul's Cathedral and the River Thames from Bankside at low tide

showing a fireplace

bronchia Plate 3 from De organis

Electrical discharge mb-artist A_Heffer by Nehemiah Grew (LondonPatterns produced by electrical discharges on surfaces revealed by dusting with powdered red lead and sulphur. Sometimes termed 'Lichtenberg figures'. These experiments were conducted at Cragside in Northumberland, England, using a Wimshurst machine (electrostatic generator) and two 10 gallon Leiden jars. Current was conveyed to two rod conductors with a spark gap at which coated wires discs or plates were positioned. Lord Armstrong exhibited figures