The field of mathematics which deals with the construction of charts representing mathematical laws is known as Nomography. Often it is necessary to repeatedly solve mathematical formulae, but with different values for the symbols involved. The manipulation of the formulae, or repeated constructions of graphs, may require considerable work, as well as carry with it the possibility of errors invalidating the results. In such a situation, the construction of a single chart which would serve for all the solutions would obviously be of considerable value.