The following are the most common symptoms of croup. However, each child may experience symptoms differently. As the disease progresses down the respiratory tract, the symptoms also change and may include: A runny nose, congestion, and slight cough. A cough develops into a seal's bark.
In contemporary use, the term Regular Army refers to the full-time active component of the United States Army, as distinguished from the Army Reserve and the Army National Guard.
Concurrent with the development of echo sounding, the C&GS developed radio acoustic ranging (RAR). Captain Nicholas Heck of the C&GS developed the concept for this system as a result of his World War I experiments in acoustic submarine detection, which he performed in cooperation with the Army Coast Artillery.