In potential theory it is often convenient to transform volume integrals over homogeneous bodies into surface integrals. The suppression of one dimension will in general simplify the calculation of the integrals. For a long time this technique has been used in magnetic field theory and the transformation is given in standard texts on potential theory (see MacMillan, 1930, section 55). The transformation appears less well known to authors concerned with the gravity method. The purpose of the present short note is to give an example of the application of this technique, a technique which appears to lead to results of practical value in the computation of the acceleration of gravity due to given bodies.