Abstract:  One approach to the magnetic field of a finite solenoid was published in this journal, which give the results in terms of infinite series. However, the convergence of the series was not examined, thus some divergence issues was overlooked. We reexamine the series and find that it is convergent everywhere outside the cylinder surface (the cylinder surface of the solenoid extended to infinity) but not inside it. The results inside the cylinder surface are recalculated, and the boundary conditions on the cylinder surface are verified.

Key words:  solenoid, magnetic field, magnetic induction, infinite series, boundary condition