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The thrill of discovery awaits you in the Smithsonian Learning Lab. From the Discovery space shuttle to the Star Spangled Banner to dinosaur fossils, the Learning Lab gives everyone with a desire to learn the opportunity to explore the Smithsonian's rich resources anytime, anywhere. Start discovering what interests you today, and find your inspiration from more than a million multimedia resources.

Suggested Discoveries

Coral Reef Official Trailer

Smithsonian Institution
This is one of our many options in our On Demand Library! Visit the link below to learn more about group packages: http://si.edu/groupsales

Postcard of Horned Dinosaur Skeletons

Smithsonian Archives - History Div
The National Museum of Natural History (NMNH) first opened to the public on March 17, 1910, as the new United States National Museum. The National Museum was first housed in what is now the Arts and Industries Building.

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."

Stuart Perry Gas Engine Patent Model

National Museum of American History
This model was submitted to the U.S. Patent Office with application for Patent no. 4800, issued October 7, 1846.

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.

Reference:

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.

Comic Book, "Action Comics"

National Museum of American History
This is an "Action Comics" Comic Book featuring Superman.

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.

Albert Einstein

National Portrait Gallery
Albert Einstein transformed the world of physics with his groundbreaking theory of relativity, and in 1921 he received the Nobel Prize for “his services to theoretical physics” and “his discovery of the law of photoelectric effect.” The German-born physicist was visiting the United States when Hitler and the Nazis came to power in his homeland in 1933. Einstein never returned to Germany. Instead, he accepted a position at the Institute for Advanced Study in Princeton, New Jersey—the newly established academic institution that would become a major center for research in theoretical physics. In residence at the institute for the remainder of his life, Einstein continued to publish, work on the interpretation of quantum theory, and wrestle without success on his unified field theory. He became a U.S. citizen in 1940.

Karsh relished the opportunity to photograph Einstein, whose face, “in all its rough grandeur, invited and challenged the camera.”

Amelia Earhart

National Portrait Gallery
A late photograph of Amelia Earhart

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.