"Inventors at Work, with Chapters on Discovery" by George Iles is a historical account written in the early 20th century. This work delves into the lives and contributions of inventors and discoverers, exploring the principles behind their inventions and the impact these advancements have had on society. It serves as both an appreciation of their innovative spirit and a discussion of the scientific, mechanical, and structural principles that underlie their creations. The opening of the book introduces the theme of the vital role inventors play in elevating human existence by transforming old methods of labor into more efficient and practical solutions. Iles highlights the importance of understanding both form and substance in invention, suggesting that effective designs lead to greater efficiency and improved functionality in various structures and tools. The initial chapter sets the stage for examining how inventions have evolved, emphasizing observation, experimentation, and the interaction between materials and designs as crucial factors in the process of invention. (This is an automatically generated summary.)