TY - JOUR T1 - Account of Pendulum Experiments Undertaken in the Harton Colliery, for the Purpose of Determining the Mean Density of the Earth JF - Philosophical Transactions of the Royal Society of London (1776-1886) VL - 146 SP - 297 EP - 355 PY - 1856/01/01/ UR - http://dx.doi.org/10.1098/rstl.1856.0015 M3 - doi:10.1098/rstl.1856.0015 AU - Airy, G. ER -