Mircea Eliade - On the number of levels and layers
Type of Spiritual Experience
He is describing visionary experience, hence, the type of experience
A description of the experience
Mircea Eliade – Shamanism Archaic techniques of ecstasy
The Vogul believe that the sky is reached by climbing a stairway of seven stars. The conception of seven heavens is general throughout southeastern Siberia. But it is not the only one found; the image of nine celestial levels, or of sixteen, seventeen, and even thirty three heavens, is not less widespread. ……. the number of heavens does not correspond to the number of gods; the correlation between the pantheon and the number of heavens sometimes seems quite forced.
Thus the Altaians speak of seven heavens, but also of twelve, sixteen or seventeen; among the Teleut the shamanic tree has sixteen incisions, representing as many celestial levels…………
V L Verbitsky found among the Altaians the idea of thirty three heavens and N V Katanov found the same conception among the Soyot. This number, however, appears very infrequently and it may be considered a recent importation, presumably of Indian origin