The M-2 Seaplane designed by the Navy Department, and built by Grover Cleveland Loening, was to have been used for submarine-patrol work. It is easily set up, and occupying so little space, can be stored aboard a submarine. The machine is a tractor monoplane with twin floats. The plane has a span of 19 feet and a total wing area of only 72 square feet. The wing section is a modified R. A. F. 15. Over-all length of machine, 13 feet. The floats are 10 feet long and weigh 16 pounds each. They are constructed of sheet aluminum with welded seams. The interior of the floats is coated with glue, and outside is not painted but coated with oil. The engine is a 3-cylinder Lawrence 60 horse-power air-cooled engine, driving a 6-foot 6-inch propeller with a 5-foot pitch. Twelve gallons of gasoline and 1 gallon of oil are carried, sufficient for two hours’ flight. Fully loaded with pilot and fuel, the complete machine weighs but 500 pounds. The maximum speed is about 100 M. P. H., and the low speed is 50 M. P. H. _Helium-Filled Model Airship_ The model dirigible exhibited by the Navy Department is inflated with helium. Another item that is of interest is the fact that this model dirigible, 32 feet long and 7 feet in diameter, contains more helium than has ever been placed in an envelope of any kind. _Astra-Torres Dirigible_ The dirigible car shown by the Navy Department is from a ship of the “Astra-Torres” type. The airship was built by the French in 1916, and turned over to the Americans in March, 1918, at Paimbœuf, France, the American naval station commanded by Commander L. H. Marfield, U. S. N. It was used until November, 1918, for coast patrol on the west coast of France. The car is 45 feet long, 6 feet wide, and 7 feet high. The envelope (which is not exhibited) is 221 feet long and 47 feet in diameter, having a capacity of 252,000 cubic feet. Speed, 45.5 miles per hour. With a crew of Americans, this ship has stayed aloft for 25 hours, 40 minutes. At its cruising speed of 45.5 miles the endurance is 10 hours. The car accommodates a crew of 12. Two 150 horse-power Renault engines with two-bladed tractor propellers are used. They are placed on outriggers. Two Lewis machine-guns are carried. The ship is one of several large dirigibles purchased by the United States navy and brought to this country for the purpose of development. B. F. GOODRICH COMPANY The principal exhibit by the Goodrich Company consisted of one of the first dirigibles put into the United States Naval Service. This is a “Blimp” that was completed in August, 1917, and used for seventeen months in coast-patrol work in the vicinity of New York City. The dirigible is 167 feet long, 33 feet in maximum diameter, and contains 80,000 cubic feet of gas. This dirigible held the record for continuous flight. A Curtiss OX motor is used. The car is arranged to carry a crew of three men. In cruising a speed of from 40 to 50 M. P. H. is maintained.