Wikipedia page about this book: https://en.wikipedia.org/wiki/Calculus_Made_Easy

Release date is 2010-07-28

"Calculus Made Easy" by Silvanus P. Thompson is a book on infinitesimal calculus originally published in 1910. Rather than relying on the traditional epsilon-delta definition of limits, Thompson takes a revolutionary approach by using direct approximation methods in the spirit of Leibniz. The book aims to demystify what are often considered terrifying mathematical concepts, making differential and integral calculus accessible through simplified explanations. Its enduring popularity is evidenced by multiple editions and numerous reprints spanning over half a century. (This is an automatically generated summary.)

Original publication data not identified