By David Grossman
Stories of Nazi super weapons have persisted since World War II, and although these are mostly fiction, they can make it seem like only the Axis had wild ideas. Not so! Winston Churchill once gave the approval for a project that almost reads like parody: aircraft carriers made out of a special type of ice.
The idea was introduced to Churchill by Lord Mountbatten, the Chief of Combined Operations for the Allies. Mountbatten had a knack for the experimental. In his short time as Chief he pushed projects like underwater pipelines and artificial coastlines made out of sunken ships. But nothing came close to his theory that a modified form of ice could be used to carry ships, potentially saving Allied forces untold amounts of metal.
His idea had scientific backing in the form of Geoffrey Pyke, an eccentric journalist and inventor. Pyke found his way into Mountbatten's war room and left a positive impression with an idea vehicle that could drive over ice, the M29 Weasel. Pyke continued to experiment with ice, alongside experts like JD Bernal and Max Perutz.
Studying the work of scientists who had fled the Nazis, they eventually came across a report that changed the entirety of their focus. Perutz, who would eventually win a Nobel Prize for Chemistry in 1962 and was working at Cambridge at the time, recalled in his autobiography that:
One day, Pyke handed me a report that he said he found hard to understand. It was by Herman Mark, my former professor of physical chemistry in Vienna, who had lost his post there when the Nazis overran Austria, and found a haven at the Polytechnic Institute of Brooklyn. As an expert on plastics, he knew that many of them were brittle when pure, but could be toughened by embedding fibres such as cellulose in them, just as concrete can be reinforced with steel wires. Mark and his assistant, Walter P. Hohenstein, stirred a little cotton wool or wood pulp—the raw material of newsprint—into water before they froze it, and found that these additions strengthened the ice dramatically.
http://www.popularmechanics.com/military/navy-ships/a27238/pykrete-ice-aircraft-carriers-wwii/