Summary: The Birth Centenary Library Volume 27 of Sri Aurobindo consists of new material discovered during the publication of his Collected Works. The supplement includes writings previously unknown, arranged subject-wise to aid references. The material is presented in its original form without editing, with blank spaces left for undecipherable parts. Sri Aurobindo's early letters signed 'Kali' reflect his transition to signing as 'K' after moving to Pondicherry. Contents include works on Vedic psychology, mystic fire hymns, Upanishads commentary, social and political thought, and writings on Bankim Chandra and other subjects. The library showcases shifting volumes to accommodate new findings and rearrange existing material, emphasizing the authenticity of Sri Aurobindo's writings. There is a focus on spiritual evolution and the synthesis of Eastern and Western thoughts, addressing challenges in modern national life. Additional content includes excerpts from translations, letters discussing financial matters, and insights into Sri Aurobindo's evolving spiritual practice and teachings, advocating patience, submission to divine will, and fortification for future actions amidst global upheavals.