Skip to main content

Scientific American

Stories by John D. Pennock

The SciencesApril 6, 1912

Losses of Combined Nitroǵen

An Important Chapter in World-Economics

John D. Pennock

Subscribe to Scientific American to learn and share the most exciting discoveries, innovations and ideas shaping our world today.

Subscription Plans Give a Gift Subscription

Explore SciAm
Latest Issue
News
Opinion
Newsletters
Podcasts
Games
Travel

Company
About
Press Room
FAQs
Contact Us
Standards & Ethics
International Editions
Advertise

More
Accessibility
Terms of Use
Privacy Policy
US State Privacy Rights
Use of cookies/Do not sell my data
Return & Refund Policy

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www.springernature.com/us). Scientific American maintains a strict policy of editorial independence in reporting developments in science to our readers.

© 2026 SCIENTIFIC AMERICAN, A DIVISION OF SPRINGER NATURE AMERICA, INC.
ALL RIGHTS RESERVED.