  A physics-first derivation of the Schwarzschild metric is given. Gravitation
is described in terms of the effects of tidal forces (or of spacetime
curvature) on the volume of a small ball of test particles (a dust ball),
freely falling after all particles were at rest with respect to each other
initially. The possibility to express Einstein's equation this way and some of
its ramifications have been enjoyably discussed by Baez and Bunn [Am. J. Phys.
73, 644 (2005)]. Since the formulation avoids the use of tensors, neither
advanced tensor calculus nor sophisticated differential geometry are needed in
the calculation. The derivation is not lengthy and it has visual appeal, so it
may be useful in teaching.
