The article reviews two books: "The Dynamical Theory of Gases" by J. H. Jeans and "A Manual of Mendelism" by Prof. James Wilson. **The Dynamical Theory of Gases**: - The book, now in its second edition, revisits the kinetic theory of gases, which has evolved over the past eleven years. - The author discusses the challenges of reconciling Boltzmann's minimum theorem with the properties of reversible units and the impact of the quantum hypothesis. - Prof. Jeans' approach is divided into four sections: mathematical theory of a gas in a steady state, physical properties of a gas in a steady state, mathematical theory of a gas not in a steady state, and physical phenomena of a gas not in a steady state. - The book also includes interesting applications, such as the rate of gas escape from planetary atmospheres, and reconciles theory with experimental data. **A Manual of Mendelism**: - Prof. Wilson's book is aimed at stock-breeders and serious students of agriculture, offering a clear and direct exposition of Mendelism. - It explains Mendel's experiments, rules, and theory, and discusses various factors that can cause abnormal character distributions. - The book highlights the improvements in agricultural productivity through careful experimentation, such as increased wheat yield and dairy production. - It emphasizes the potential of Mendelian principles to enhance material wealth and encourages readers to study the book for practical applications.The article reviews two books: "The Dynamical Theory of Gases" by J. H. Jeans and "A Manual of Mendelism" by Prof. James Wilson. **The Dynamical Theory of Gases**: - The book, now in its second edition, revisits the kinetic theory of gases, which has evolved over the past eleven years. - The author discusses the challenges of reconciling Boltzmann's minimum theorem with the properties of reversible units and the impact of the quantum hypothesis. - Prof. Jeans' approach is divided into four sections: mathematical theory of a gas in a steady state, physical properties of a gas in a steady state, mathematical theory of a gas not in a steady state, and physical phenomena of a gas not in a steady state. - The book also includes interesting applications, such as the rate of gas escape from planetary atmospheres, and reconciles theory with experimental data. **A Manual of Mendelism**: - Prof. Wilson's book is aimed at stock-breeders and serious students of agriculture, offering a clear and direct exposition of Mendelism. - It explains Mendel's experiments, rules, and theory, and discusses various factors that can cause abnormal character distributions. - The book highlights the improvements in agricultural productivity through careful experimentation, such as increased wheat yield and dairy production. - It emphasizes the potential of Mendelian principles to enhance material wealth and encourages readers to study the book for practical applications.