Comment on "Gauge transformations are Canonical transformations"

We comment on the work of Tai L Chow, Eur. J. Phys. 18, 467 (1997). By considering the Lagrangians which are uniquely defined only to within an additive total time derivative of a function of co-ordinates and time the author has tried to show that the gauge transformations which relate these Lagrangians are canonical transformations. He has obtained the right conclusion only by using wrong canonical equations and the entire exercise has hence become erroneous and inconclusive. By using the definition of canonical transformation through Poisson brackets we prove that the above gauge transformations are canonical transformations.