December 2025: Science History from 50, 100 and 150 Years Ago

Heimlich maneuver; training fleas

A colorful microstructure

1975, Plastic Crystal: “Typical microstructure features observed in semi­crystalline polymers can be seen in this photomicrograph of a thin film of polypropylene. The ‘sunburst’ structures are called spherulites; their boundaries would be circular if they did not encounter neighboring crystallites as they grow outward from a core. The photomicrograph was made by David Hamer at the Celanese Research Company.”

Scientific American, Vol. 233, No. 6; December 1975

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1975

Heimlich Maneuver

“The list of first-aid procedures that the medical profession encourages laypeople to undertake is short because of concern that tactics applied in ignorance may do more harm than good. Now, however, the American Medical Association has cautiously endorsed the ‘Heimlich maneuver’ as a first-aid procedure when someone is choking on a foreign object, described by Henry J. Heimlich, the Cincinnati surgeon who developed it. In the Heimlich maneuver, you get behind the victim and wrap your arms around their waist, put the thumb side of your fist or the heel of your palm against the victim’s upper abdomen, between the navel and the bottom of the rib cage, and make a quick upward thrust. The action elevates the diaphragm, thereby compressing the lungs and forcing air up through the trachea. The air expels the foreign object. Heimlich writes that since he first described the technique he has heard of 162 people whose lives were saved.”


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1925

Exhausted Universe

“What has science to say of the future? The physicist can tell us that the universe is ‘running down,’ for heat tends to escape by radiation from the surfaces of the stars, planets and all other bodies. Slowly, then, all things must cool down, depleted to the point of exhaustion, so that the final scene of the play shows only cold, dark bodies, frozen, rigid and lifeless, moving in their orbits in impenetrable darkness. Most completely irreversible would appear to be the newly discovered process by which matter is turned into free energy. Thus also before the last gleams of light disappear the principal actors—the stars—have dwindled away to mere shrunken remnants of their old selves.”

Telephone Diplomacy

“Embassies and consulates, university scholarships, lecture tours, propaganda—all have had for years as their supreme object a better understanding, a closer friendship between America and the Old World. Now comes the announcement that soon you may pick up your telephone and talk with a person in London as easily as if they were in the next street. What is more, you can do this at a cost of five dollars for three minutes. Here is an achievement which outweighs a century of striving for international accord. When people talk directly to one another easily, cheaply and constantly about their daily affairs, it becomes more and more difficult for them to misunderstand each other. As an insurance of peace, the inauguration of the five-dollar, three-minute transatlantic telephone rate may well rank with the best treaty ever signed.”

1875

New Route to Siberia

“Professor Nordenskiöld’s recent journey from Norway to Siberia, by way of the Yugorsky Strait and the Sea of Kara, has caused quite a sensation in Russia. At a meeting of the Society for the Encouragement of Commerce and Industry, Mr. Sidorov said the journey was one to be ranked in importance with the discovery of a new world, as it would in all probability lead to the establishment of a regular line of communication between northern Europe and Siberia, and the vast resources of the latter country would at last find an outlet along her great fluvial highways.”

Training Fleas

“Mr. Bertolotto, the well-known educator of the flea, is now in New York exhibiting his curious success. The insect he employs appears to be the species of flea common to dogs. The first lesson, he says, is to put the fleas in a small circular glass box, where, by jumping and knocking their heads against the glass for a day or two, the idea is finally beaten into them that it is useless to jump. During the remainder of their natural lives—about eight months—they are content to crawl.

The instructor then fastens a delicate pair of wire nippers to the middle of the flea’s body; to the nippers any desired form of miniature vehicle, such as a wheelbarrow, car or wagon, is attached, and the flea trots away with the load. The professor harnesses his insect pupils to perform many curious duties, such as the operation of a fortune-telling wheel, orchestra playing or racing. The fleas are allowed to feed twice daily upon the instructor’s arm.”

Three covers of Scientific American from December 1975, 1925 and 1875

Mark Fischetti was a senior editor at Scientific American for nearly 20 years and covered sustainability issues, including climate, environment, energy, and more. He assigned and edited feature articles and news by journalists and scientists and also wrote in those formats. He was founding managing editor of two spin-off magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 article “Drowning New Orleans” predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. Fischetti has written as a freelancer for the New York Times, Sports Illustrated, Smithsonian and many other outlets. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti has a physics degree and has twice served as Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union’s Robert C. Cowen Award for Sustained Achievement in Science Journalism. He has appeared on NBC’s Meet the Press, CNN, the History Channel, NPR News and many radio stations.

More by Mark Fischetti
Scientific American Magazine Vol 333 Issue 5This article was published with the title “50, 100 & 150 Years” in Scientific American Magazine Vol. 333 No. 5 (), p. 92
doi:10.1038/scientificamerican122025-53aFjqkMFqWqQiiJ1zW5Kx

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