"Tables of Physical and Chemical Constants" (4th edition), by G. W. C. Kaye and T. H. Laby, published by Longmans, Green & Co. in 1921, is a valuable resource for physicists and related sciences. The book has reached its fourth edition after nearly ten years, which is a significant achievement. The authors have carefully selected a vast amount of data, making the book more useful than other larger data collections. The book includes references to the sources of the information, allowing for easy verification. This edition has been thoroughly revised and includes additional pages. Notably, sections on X-ray wavelengths and sparking voltages have been updated, and tables on heat and gravity constants have been expanded. The atomic weights in the book have been recalculated based on the latest values from the International Atomic Weight Committee. The reviewer's experience with previous editions shows that the values are remarkably accurate. The book provides extensive information on the physical constants of commonly used materials. It also highlights the lack of experimental data on some useful constants of substances used in laboratories and industries, emphasizing the need to fill these knowledge gaps."Tables of Physical and Chemical Constants" (4th edition), by G. W. C. Kaye and T. H. Laby, published by Longmans, Green & Co. in 1921, is a valuable resource for physicists and related sciences. The book has reached its fourth edition after nearly ten years, which is a significant achievement. The authors have carefully selected a vast amount of data, making the book more useful than other larger data collections. The book includes references to the sources of the information, allowing for easy verification. This edition has been thoroughly revised and includes additional pages. Notably, sections on X-ray wavelengths and sparking voltages have been updated, and tables on heat and gravity constants have been expanded. The atomic weights in the book have been recalculated based on the latest values from the International Atomic Weight Committee. The reviewer's experience with previous editions shows that the values are remarkably accurate. The book provides extensive information on the physical constants of commonly used materials. It also highlights the lack of experimental data on some useful constants of substances used in laboratories and industries, emphasizing the need to fill these knowledge gaps.