The Constantin Kluge - Pierre Leroy collection consists of 34 personal, autograph signed letters from Father Leroy to his friend Constantin Kluge, in addition to first-hand background information provided by Kluge on his acquaintance with Pierre Teilhard de Chardin and his circle (especially Pierre Leroy and Claude Riviere). A complete typed transcription of the 34 letters has been graciously provided by Mme. Solange Soulie, a close friend of Pierre Leroy.