This book was published on the occasion of celebration of 100 years of IACS in 1976. This is an important and enriched document to know the formative period and history of IACS. The coverage of this book had been classified into four distinct periods: 1. The Early Perid 2. The Period of Prof. C V Raman 3. The Period of Prof. K S Krishnan 4. Post Independence PeriodFinancial assistance was given from Govt. of India & Govt. of W.B. to the Steering Committee for the Centenary Celebration of IACS under Prof. D. Basu, Directo