"Scientific American popular science supplement No. 819, September 12, 1891" - a publication that collected the most interesting and relevant articles from various fields of science and technology of that time. The authors of this book are various experts and scientists. In this issue, readers will find information on the latest advances in medicine, physics, chemistry, engineering, and more. Each article contains a large amount of interesting and useful material that will allow you to delve deeper into the world of science of that period. Scientific American Supplement no. 819, September 12, 1891 - an integral part of the book heritage, which remains relevant and interesting to this day.