Editor’s note (4/2/2017): This week marks the 100-year anniversary of the U.S. entry into the First World War. Scientific American, founded in 1845, spent the war years covering the monumental innovations that changed the course of history, from the first tanks and aerial combat to the first widespread attacks with chemical weapons. To mark the centennial, we are republishing the article below and many others. For full access to our archival coverage of the Great War sign up for an All Access subscription today.

Reports and opinions in Scientific American on a key tragedy in World War I
May 8, 2015

When the German submarine U-20 torpedoed the British civilian ship Lusitania on May 7, 1915, the grand ocean liner sank in only 18 minutes. Behind the outrage caused by the death of 1,193 people, including 128 Americans, there were questions. The ship sank so fast that only 767 people survived: why did it go down so fast? In the diplomatic furore that followed, the German government claimed that the disaster had occurred not because of their one torpedo, but because military stores being carried by the ship had detonated, bolstering their assertion that the Lusitania was really a munitions-carrying naval ship masquerading as a peaceful civilian ocean liner. The editorial in Scientific American in the May 29, 1915, issue, vehemently disagreed on technical grounds:

The grand RMS Lusitania as the vessel appeared in 1907, shortly after being launched. Image: Scientific American, August 10, 1907

“In its endeavor to becloud the issue, official Germany has claimed that the ammunition carried by the ‘Lusitania’ contributed largely to the swift sinking of that great ship. Now this is a technical question, and to anyone who is technically qualified to judge the matter, the explanation offered is, on the face of it, absurd. This war has proved over and over again that one submarine torpedo of the German type, carrying 420 pounds of high explosive, is sufficient to sink a warship–even a battleship which, exclusive of the double bottom deck, is divided into no less than two hundred and fifty separate watertight compartments, big and small.”
[Scientific American, May 29, 1915]

Despite this stern editorial rebuke it is evident that doubts abounded. The ship was, after all, acknowledged to be carrying 4,000 cases of rifle ammunition (at a thousand rounds a case) made by Remington. Trade in such military materiel was legal between a neutral country and a belligerent, but perhaps there were questions on whether all that ammunition had contributed to the disaster. Five weeks after the sinking, an article with a more thorough treatment of what can happen with all that live rifle ammunition: even with 4 million rounds, not much:

“We have shown in a previous issue that a single submarine torpedo because of its enormous charge of explosive was quite sufficient to sink the ‘Lusitania’ in the short period of time which elapsed between the blow of the torpedo and the disappearance of the ship. The German government has suggested that the rapid disappearance of the ship was due, in part at least, to the explosion of the cargo of ammunition which it carried. To a military man, or indeed to anyone with a fair knowledge of explosives, the suggestion is ridiculous; for the ammunition in the hold of the ship consisted of unloaded shells, and of small-arms ammunition packed in cases which cannot be exploded by any known means. Some years ago the Winchester Repeating Arms Company, in order to prove that small-arms ammunition could be transported with perfect safety, undertook a series of severe tests to show that such ammunition packed in the ordinary cases was incapable of being exploded either by shock or flame; and we publish herewith a series of photographs of the ammunition as it appeared after passing through the test.”
[Scientific American, June 12, 1915]

In a test of small-arms ammunition, cases of shells were dropped, smashed, burned and in this test, blasted three times with a shotgun. Two of the cartridges in the case were ignited, but the nitrocellulose smokeless powder burned slowly and they soon extinguished themselves. Image: Scientific American, June 12, 1915

Germany saw streams of cargo–ammunition, guns, food–being shipped to their enemies while they themselves suffered behind the British Royal Navy’s blockade, and until the beginning of 1917 followed a vacillating policy on submarine warfare. The editorial in Scientific American of July 31, 1915, has a strong reaction to these policies. It also shows that none of the anger about the Lusitania had dissipated (bear in mind that the Allies benefited greatly from such anger about the submarine attacks by the Central Powers, and have often been accused of stoking it):

“The warning issued by the German Ambassador before the sailing of the ‘Lusitania’ indicates quite clearly what the intention of the Imperial government was with reference to this act. That Germany has no intention to depart from its crusade against passenger steamers is evidenced by the attempts that have been made against the ‘Orduna.’ Owing to the fact that no lives were lost in the attack upon this steamer, comparatively little attention has been directed toward the significance of the act. Although this vessel escaped the fate of the ‘Lusitania,’ the crime against humanity was almost greater than in the disaster to the latter. Practically the only excuse which has been made by German apologists for the destruction of the ‘Lusitania’ and the loss of so many hundreds of lives, was the charge that she carried guns, which has been disproved, and that she carried ammunition, which has been admitted, but in the case of the ‘Orduna’ no such reasons have been given, and the act stands forth, therefore, in its flagrant nakedness. Not only have the officers on the watch testified to the fact that they saw the torpedo, but it was only by the narrow margin of ten feet that the German submarine failed to expose the Americans on board the ‘Orduna’ to the same fate as befell our citizens on board the ‘Lusitania.’”
[Scientific American, July 31, 1915]

The United States declared war on Germany on April 4, 1917. One of the many reasons was the German policy of submarine attacks on neutral ships–the most prominent example of which was the Lusitania. Even after the war ended, justification for hostilities was still being found in the Lusitania sinking:

“An act of outrage and terrorism like the destruction of the Lusitania, with its awful loss of life, did more to rouse and stiffen American feeling than any single measure that could have been conceived. As Joseph Fouch? [minister of police under Napoleon Bonaparte] said, it was more than a crime; it was a political fault, and that of the most egregious kind. The extravagant jubilation with which the crime was everywhere hailed in Germany was the finishing touch to the episode, and greatly intensified the wrathful indignation that and disgust of civilized humanity. It was significant that the American troops should go into action with the battle-cry of ‘Lusitania!’”
[Scientific American, May 10, 1919]

But if the sinking of the Lusitania is one of the key events that prompted the entry of the U.S. into World War I on the side of England, France and Russia, then it has also been a lightning rod for conspiracy theories for a century, turning on the question of the second muffled explosion and whether the blast proves that Germany was justified in claiming that the ship was carrying more munitions than were listed on the cargo manifest. There have been rumors that some of the cargo that was listed as “cheese” or “oysters”, perhaps, was in truth explosives, carried aboard with a “nod and a wink.” In fact as late as 1982 there were individuals at the United Kingdom’s Foreign & Commonwealth Office who thought that it was possible that the wreck of the Lusitania on the ocean floor might contain still-dangerous explosives, and warned salvage divers of that fact. Then again, there were witnesses who thought they saw two torpedoes fired at the ship. The German submarine’s captain, crew and log say they only fired one torpedo. Unless they fired two and–with “a nod and a wink” and a dire threat of severe punishment–they were warned not to say anything else.

But it seems silly to conjure conspiracy theories from the murk of wartime propaganda, nationalist sentiment and even amid the current Internet-fueled enthusiasm for such theories: the cargo manifest lists 50 barrels of aluminum powder and 50 barrels of bronze powder. Both of these powders, if fine enough, and thrown into the air, say, by a torpedo explosion, present an explosion hazard. This from the Aluminum.org Web site: “In the case of aluminum, explosions can result if ignition occurs while particles are suspended in the air as a dust cloud, as the burning extends from one particle to another with extreme speed.” The same with bronze powder. And when these powders come into contact with water (perhaps, say, seawater rushing in through a gash in a boat hull), they both give off hydrogen gas, which, as we remember from the Hindenburg disaster of 1937, is explosively flammable. It seems likely that a few barrels of ordinary cargo and common chemistry helped one torpedo sink this grand ocean liner. But arguments about cause aside, the loss of this ship full of civilians still ranks as one of the many tragedies of the Great War for Civilization.

See the first installment of this post here.


Our full archive of the war, called Scientific American Chronicles: World War I, has many articles from 1914-1918 on artillery. It is available for purchase at www.scientificamerican.com/products/world-war-i/