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Grayscale postcard of two skeletons of horned dinosaurs on exhibit at the United States National Museum, now the National Museum of Natural History. The larger one is a Triceratops skeleton, and the smaller one is a Brachyceratops skeleton. The postcard is unused, but the message side has a printed note about the dinosaurs: "These skeletons of two extinct reptiles known as Horned Dinosaurs were discovered in the Cretaceous rocks of the West. Triceratops, the larger of the two specimens, shown, named for the three horns on its head, was about 20 feet long. With a head 6 feet in length it had the largest skull of any known reptile. The other skeleton, Brachyceratops, less in size than the skull of the Triceratops, is the smallest of North American horned dinosaurs. Both of these animals were plant eaters, living in the swamps of the western plains. They became extinct over 100,000,000 years ago."
This engine is very similar to the Perry engine of 1844 (US National Museum accession number 309253). It differs in that the cylinder is water-jacketed and the hot cooling water is used to heat the fuel retort. Ignition is effected by heated platinum exposed to or separated from the explosive mixture by a valve.
The model shows a horizontal double-acting engine completely water-jacketed. Beside the cylinder is the retort for generating the vapors. Air is mixed with the vapor in a valve box above the retort, and valves operated by cams from a lay shaft admit the explosive mixture to passages leading to the cylinder. The gas is ignited by incandescent platinum, and combustion continues during about one-third of the stroke, the expansion of the products of combustion forcing the piston to the end of the stroke.
To start the engine it was necessary to heat the water about the retort to generate the vapor and to heat the igniter. When running, the engine developed sufficient heat for both purposes.
Perry designed this engine so that the water served not only to cool the cylinder but also to lubricate the piston and piston rod.
This description comes from the 1939 Catalog of the Mechanical Collections of the Division of Engineering United States Museum Bulletin 173 by Frank A. Taylor.
Superman’s June 1938 appearance in Action Comics No. 1 gave birth to the superhero genre. Superman used his extraordinary powers to fight for “truth and justice.” The character’s popularity led to the creation of other costumed crime fighters such as Batman and Captain Marvel.
Karsh relished the opportunity to photograph Einstein, whose face, “in all its rough grandeur, invited and challenged the camera.”
To locate tiny Howland Island, Earhart and Fred Noonan expected to communicate with the Itasca, a United States Coast Guard cutter that President Roosevelt agreed to locate near the island for assistance. Although the cutter received messages, at first faint but then clearer and stronger, communication ultimately failed. Upon learning that the pair had not arrived, Roosevelt ordered a massive sea and air search that went on for more than two weeks. When that search was terminated, George Putnam underwrote his own search that lasted until October. Newspapers around the globe covered the search on a nearly daily basis. Yet as time elapsed, hope for their safe recovery faded. In 1939, a probate court in Los Angeles declared Earhart legally dead. Neither the plane nor the bodies of the two pilots have ever been recovered.