Public domain
Air engine tester. Dr. K.C. Dickinson, Chief of the Heat and Power Division of the Bureau of Standards, and the control room of the new aircraft engine testing laboratory at Arlington, VA. Here all engines for use on licensed airplanes are to be tested and to protect the observer, the control room a
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineAir engine tester. Dr. K.C. Dickinson, Chief of the Heat and Power Division of the Bureau of Standards, and the control room of the new aircraft engine testing laboratory at Arlington, VA. Here all en. 1929-01-01. Harris & Ewing. Harris & Ewing Collection, Library of Congress. Public domain.
Similar works
![Dr. J. Harris Rogers, of Hyattsville, MD., inventor of underground and under water radio communication systems, is shown with the loop antenna he used recently in receiving signals from [...] the Atlantic Ocean, this loop was submerged as well](https://thumbs.arkivism.com/loc-2016887622.jpg)
Dr. J. Harris Rogers, of Hyattsville, MD., inventor of underground and under water radio communication systems, is shown with the loop antenna he used recently in receiving signals from [...] the Atlantic Ocean, this loop was submerged as well
No Caption
Heinrich Beck
Dr. D.C. Bardwell, of the Research Lab. of the U.S. Bureau of Mines, collecting gaseous radium emanation. The radium is in the little safe at the right. Collections are made at intervals of from 4 to 10 days. The gas is drawn off under vacuum and purified by a liquid air refrigeration. The purified
The latest in radio development which has been perfected by Mr. H.P. O'Reilly of Wash., D.C.
Man with scientific instruments