  The 9.2 keV nuclear transition in $^{227}$Th populated in the $\beta$-decay
of $^{227}$Ac was studied by means of the internal conversion electron
spectroscopy. Its multipolarity was proved to be of mixed character M1+E2 and
the spectroscopic admixture parameter $\delta^2$(E2/M1)=0.695 $\pm$ 0.248
(|$\delta$(E2/M1)|=0.834 $\pm$ 0.210) was determined. Nonzero value of
$\delta$(E2/M1) raises a question about the existing theoretical interpretation
of low-lying levels of $^{227}$Th.
