Liberty Ships Live On
What a fine Winter 1988 issue! As a maritime historian I wanted to offer you a little additional information relating to James R. Chiles’s “The Ships That Broke Hitler’s Blockade.”
Mr. Chiles is quite right that the Jeremiah O’Brien , in San Francisco, is the only Liberty ship your readers can see, but others are still in existence. A few years ago one former Liberty was spotted in the Orient, and while little is known about her operations, she was sailing strong as the Zhong Hua . With the supply of parts long gone, crafty mechanics the world over have still been able to repair the Liberty because she is a simple, basic ship.
Allan E. Jordan
Roslyn Estates, N. Y.
Liberty Ships Live On
I was interested in Mr. Chiles’s discussion of the cracks in Liberty ships. In 1952 I had the responsibility for writing the definitive report on the Liberty-ship failures, based on work I had done or supervised at the Naval Research Laboratory and on the work of others at the National Bureau of Standards. The report described in detail the improvement possible through changes in the chemical composition of steel. The changes couldn’t be made in time to affect the Liberty ships; the Liberty failure problem was controlled by the changes in design that Chiles mentions—including rounded hatch corners—and improvements in welding practice.
We now understand that failures of this general class are usually a consequence of a combination of problems, including poor design that leads to high local stress, operating conditions that superimpose a dynamic load, the existence of a fatigue or stress-corrosion or thermal crack, and a material that is brittle at operating temperatures. Thus solutions can be achieved by a variety of approaches. We were fortunate that such was the case with the Liberty ships.
It was rewarding to read such a comprehensive and accurate commentary on the Liberty-ship construction effort.
William J. Harris
E. B. Snead Professor of Transportation Engineering
Texas A&M University
College Station, Tex.
The American Can That Could
Richard M. Daniel alters the circumstances of the development of the U.S. version of the jerrycan in “The Little Can That Could” (“Postfix,” Fall 1987).
Britain captured samples of Wehrmacht fuel containers along with other Nazi equipment in 1940. The handiness of these cans was apparent at once, so some were sent to the U.S. office of the Quartermaster General. They were found to be stackable, light, strong, and useful with any fuel, have an excellent handle and spout, and need no accessories. But it became obvious that the can was designed to be assembled by hand labor in small shops rather than on a mass scale in large factories. This did not suit American industrial methods or the urgent need for the cans, so the Quartermaster Depot opted for a can to be built the American way.
Because twenty liters meant nothing, the can was redesigned for a capacity of five U.S. gallons. Rather than being made of two similar pieces welded along the center line, it was made of three parts with welded seams and a rolled-on bottom. The German camstyle spout was dropped in favor of the threaded top found on old U.S. containers. In the end there was one feature common to the German and U.S. cans—a three-bar handle on top.
By autumn 1940 the U.S. Quartermaster Corps had awarded contracts to four firms for the new can. Production was high enough that every jeep produced after August 1, 1942, came with a spare gas can attached. During 1943, 1944, and 1945, twenty-two million U.S.-pattern cans were produced. Shortly after D-day, in June 1944, a severe shortage of the cans developed throughout the Allied units in Europe; this was cured by the shipment of millions of British “jerricans,” which were nearly identical copies of the original German twenty-liter can.
The “tin can” construction of the American can proved ideal for a highvolume product, and less than one percent were found to leak. It is true that the German cam-lock was easier to use than the threaded cap and flexible nozzle—except for filling the tank of a jeep. The jeep’s filler tube was under the driver’s seat, inside the vehicle.
Bucky Vs. Hughes
In your Winter 1988 issue there is an interesting contrast between “Who Was Buckminster Fuller, Anyway?,” by Amy Edmondson, and “The Industrial Revolution That Never Came,” by Thomas P. Hughes.
Ms. Edmondson’s portrait of Fuller reminded me of how he passionately believed that technology could help reform human society.
Dr. Hughes would probably label such a belief “technological determinism,” arguing that social forces make it impossible for “visionaries” like Bucky to predict the “messy social changes” that will accompany any applied technology. And to illustrate the illusory ideals that people attach to technology, Hughes tells the story of the 1920s’ hopes for electric-power grids.
How ironic that Bucky’s first World Game seminar, in New York in 1969, chose a worldwide electric grid as its exemplar of how technology could refashion the earth for the welfare of all!
Vincent W. Hevern, S.J.
New York, N.Y.