  A simple analysis is presented of the particular experiment used to prove the
bulk nature of very-high-Tc superconductivity in H3S compound under ultra-high
pressure. In the experiment, an internal magnetic field was sensed by the
synchrotron M\"ossbauer spectroscopy in tin placed inside the H2S sample. The
experiment showed peculiar anisotropy with respect to the direction of the
applied field at first sight. By considering actual experimental geometries and
parameters of the experiment, we show that this particular observation is
consistent with the expectations for a regular type-II superconductor with
Meissner expulsion and pinning.
