Before there was Valentin Tomberg, there was Gregory Ottonovich Mebes, or G.O.M. He led an esoteric school in St. Petersburg, from which we get his own Meditations on the Major Arcana of the Tarot.
In Meditations on the Tarot (MotT), Tomberg describes his encounter with that school:
At St. Petersburg in Russia, around fifty years ago, there was a group of esotericists who composed the flower of the capital’s “intelligentsia”. This group was internally hierarchical, i.e. it comprised “grades” — Martinist, Templar and Rosicrucian. It was, properly said, a school of teaching and training comprising three “courses” or “classes”—first or Martinist, second or Templar, and highest or Rosicrucian.
At the head of the whole school was the professor of special mathematics from Pages College in St. Petersburg, Professor Gregory Ottonovitch Mebes.after the Bolshevik revolution (which, it goes without saying, put an end to this group and its work) that the one who is writing these lines met some members of this dispersed group and became friends with them. The friendship being true, i.e. based on unreserved mutual confidence, they (who belonged to the so-called “Rosicrucian” elite of the group) transmitted all that they knew and recounted everything concerning the work of their group, including the crises and painful experiences that they had undergone. This was in 1920.
[Tomberg] was struck to learn to what degree collective work on the Tarot can be fruitful for study, research, training and advancement in the esoteric domain. For the whole work of the Martinist-Templar-Rosicrucian group was founded on the Tarot. Study of the Cabbala, Magic, Astrology, Alchemy and Hermeticism was guided and inspired by the Tarot. This gave the whole work an exceptional coherence and organic unity. Every problem concerning the Cabbala, Magic, Astrology, Alchemy, etc., was treated as relating to a particular Arcanum of the Tarot.
the teaching and the experiences of this group of St. Petersburg esotericists lives now in the soul of the author of these Letters only as a general impulse received in his youth to penetrate the symbolism of the Tarot more deeply
As any original copies of G.O.M.’s works were destroyed by the Bolsheviks, the only source of his teachings were in the form of notes take by one of his pupils. Somehow these ended up in Brazil where they were translated into Portuguese.
The good news is that these notes are now available in English with extensive notes and additional commentary for each Arcanum. Charlotte (she does not identify herself in the printed book) and others painstakingly compiled this work, which is available on Amazon here: Tarot Majors: G.O.M. Since it is print on demand, you should be able to find it on the Amazon for your country.
This book is highly recommended for those working closely with MotT.