English: Drawing of torsion balance apparatus used by Henry Cavendish in the 'Cavendish Experiment' to measure the gravitational constant in 1798. This is a vertical section through the apparatus, including the building that housed it. Copy of Figure 1 from his 1798 paper 'Experiments to determine the Density of the Earth' published in Philosophical Transactions of the Royal Society of London, (part II) 88 p.469-526 (21 June 1798). Alterations: removed frame and caption, compensated for shear distortion caused by scanning book, converted to PNG.