He was one of a new breed of multi-disciplinary scientists studying the biology and ecology of plant life. His research work was concentrated on water retention of soils and he was a founder of the science of soil physics. In 1906 he devised a soil classification technique called the moisture equivalent based on centrifuging, which is now thought of as the first Pedotransfer function. In the same year he also organized a biophysical laboratory that later became the Bureau of Plant Industry. Briggs worked with Homer Leroy Shantz on the effect of environment on the water uptake by plants, and was an early contributor to ecology. World War I Briggs was detailed by an Executive Order to the Department of Commerce's Bureau of Standards in 1917 due to mobilization pressures of World War I. There he developed an artificial horizon device for naval vessels with John Hayford which established a stable zenith independent of the roll of the vessel for the aiming of naval guns. This allowed for the roll of the ship to be observed, so that the firing of the guns could be timed with the roll of the ship. The device was so successful it found its way into the control rooms of most naval vessels. A confidential report called the Hayford–Briggs report was given to the Navy, but never published. National Bureau of Standards (1917–1945) In 1920 Briggs officially left the Department of Agriculture and joined the National Bureau of Standards, where he was chief of the Engineering Physics Division (later the Mechanics and Sound Division). He appointed Hugh L. Dryden to head the Aerodynamics Physics Section, and together they pioneered research in the aerodynamics of airfoils moving near the speed of sound in an airstream. This work had significant application in developing blade forms for aircraft propellers. He also retained an interest in navigational devices, and with Paul R. Heyl invented the Heyl–Briggs earth inductor compass. The compass used a spinning electric coil subjected to the magnetic field of the Earth to determine the bearing of an airplane in relation to the Earth's magnetic field. For this invention, they received the Magellan Medal of the American Philosophical Society in 1922. This type of compass was used by Admiral Byrd in his flight to the North Pole and by Charles Lindbergh on his 1927 trans-Atlantic flight. In 1926 Briggs was appointed assistant director for research and