  The core theorem on which the above paper is centred - that a perfectly
conducting body of revolution absorbs no angular momentum from an axisymmetric
electromagnetic wave field - is in fact a special case of a more general result
in electromagnetic scattering theory. In addition, the scaling of the
efficiency of transfer of angular momentum to an object with the wavelength and
object size merits further discussion. Finally, some comments are made on the
choice of terminology and the erroneous statement that a circularly polarized
plane wave does not carry angular momentum.

Optics