Summary: The book "Direct Current Geoelectric Sounding Principles and Interpretation" by Bhattacharya and Patra focuses on resistivity sounding techniques for exploration in geology and geophysics. Geared towards students and professionals, the book covers various methods including dipole sounding, Schlumberger, and Wenner arrangements, providing theoretical foundations and interpretation guidelines. Practical applications such as mineral exploration, groundwater prospecting, and structural mapping for oil are discussed, emphasizing the utility of resistivity sounding in civil engineering, agriculture, and resource exploration. Detailed calculation procedures for multi-layer earth resistivity and interpretation of field curves aid in mapping underground features. The book includes examples with field curves and corresponding geological sections, showcasing the use of resistivity measurements for subsurface investigations in diverse geological settings. Overall, the book presents a comprehensive guide for conducting and interpreting DC resistivity surveys for geological and geophysical exploration.