  The Kolmogorov equation with a forcing term is compared to experimental
measurements, in low temperature helium gas, in a range of microscale Reynolds
numbers $R_{\lambda}$ between 120 and 1200. We show that the relation is
accurately verified by the experiment (i.e. within +/- 3 % relative error, over
ranges of scales extending up to three decades). Two scales are extracted from
the analysis, and revealed experimentally, one characterizing the external
forcing, and the other, varying as $R_{\lambda}^{-3/5}$, defining the position
of the maximum of the function $- S_{3}(r)/r$, and for which a physical
interpretation is offered.
