The book "Appletons' Popular Scientific Monthly, April 1900, Volume 56, November 1899 - April 1900" is a collection of scientific articles by various authors in various fields of knowledge. This publication presents articles that reveal new discoveries and theories of science and natural sciences at the end of the 19th century. Readers will have the opportunity to deepen their knowledge of physics, chemistry, biology, astronomy and other disciplines through this outstanding scientific journal. Each article is marked by a high level of research and accurate information, making this publication a valuable source of knowledge for any seeker of true scientific information. Appletons' Popular Science Monthly is deservedly considered one of the most authoritative scientific publications of its time and a valuable document for further scientific research and the study of the history of science.