It is true that some weapons were aboard, Ms. Preston said. The ship’s manifest made no secret that it carried weapons in its hold, including 4,200 cases of Remington rifle cartridges and 1,250 cases of shrapnel shells and fuses. But they would not have caused the kind of volcanic one-two punch that doomed the ship, she said.
Furthermore, she said, a 1993 expedition by the explorer Bob Ballard indicated there had been no explosion in the area of the ship where those weapons were stored.
“That doesn’t mean, of course, there weren’t other things on board that could have been stored somewhere else, but no one has ever produced evidence of that,” Ms. Preston said.
Speculation over a secret cargo intensified in 2014, when Britain released government documents from 1982 that warned a proposed salvage mission to the wreck could “literally blow up on us.”
“The facts are that there is a large amount of ammunition in the wreck, some of which is highly dangerous,” Noel Marshall, the head of the Foreign Office’s North America department, wrote at the time, according to The Guardian.
He added that to warn the salvage company of the risk would mean “the first acknowledgment of the facts” by the government. In the end, no warning was given and Britain’s official story never changed.
In her book “Lusitania: An Epic Tragedy,” Ms. Preston argued the explosion was caused by the sudden impact of frigid North Atlantic water on the ship’s steam lines.
“There are all these theories, and people will argue about it, but my own belief is that it is actually the steam lines that did it,” she said. “And certainly whatever the British and German governments said about it afterward — in spite of accusations and counter accusations — nobody really knew either. Everybody was very puzzled.”
The newly retrieved telegraph is unlikely to solve that puzzle. Heather Humphreys, Ireland’s minister of culture, heritage and the Gaeltacht, called the telegraph an “important piece of the Lusitania” and said it was “undamaged and in excellent condition.”
The ministry said that because the artifact facilitated communication between the bridge and the engine room, it…