Graphical solution for high-angle fire

The point of the following methods is the reduction of the calculation of the path of a shell in high-angle fire to processes which can be either graphically constructed or calculated, once and for all, the results applying to all trajectories and shells of any ballistic constant. It is assumed that the law of resistance R(v ) is largely empirical, and is not to be reduced to any neat mathematical formula. Furthermore the variation of the density of the atmosphere is taken account of, and its dependence on the height is assumed to be given by some empirical formula.