Experimental equipment to test electrical conductivity in a vacuum mb-code 584DA Framed as if on individual

Framed as if on individual sheets of paper and signed below 'A

Lansdowne House in Berkeley Square

'The Rod Still in Pickle'

'First Stage of Cruelty'

The sitter's right hand can be seen holding a paper

Experimental equipment to test electrical conductivity in a vacuum mb-code 584DA Framed as if on individualPlate 9 figures 1 2 from the paper 'Electrical experiments made in order to ascertain the non conducting power of a perfect vacuum', by William Morgan, Philosophical Transactions of the Royal Society, vol. 75 (1785), pp. 272 278. Figure 1 shows a 15 inch mercury gauge partially coated with tin foil, emptied of air and inverted into a mercury cistern. A wire is visible within this reservoir, through which an electrical current was passed but without