In the experiments of Jamieson and Pleissner on the pressures in deep grain bins[Footnote 15] ], the ratio,
, of the lateral unit pressure,
, on a vertical plane to the vertical unit pressure,
, on a horizontal plane, was found by Pleissner to vary from 0.3 to 0.5 and by Jamieson to equal 0.6, for wheat in wooden bins of various sizes.
This ratio,
, increases somewhat with the depth of the grain, but the increase is slight after a depth of from 2½ to 3 times the width or diameter of the bin is reached.