The article “Bar Codes Sweep the World” (Spring 1993) was interesting and very flattering to Bob Silver and Joe Woodland. However, it was also misleading. An analogy would be an article that implied that Leonardo da Vinci and Samuel Langley had invented the airplane (when in fact they only built models that couldn’t fly) and didn’t even mention the Wright brothers.
The main keys to a practical bar-code system were the laser, an elegant barcode design, and a scanner using mirrors to fold the scanning beam, allowing a linear bar code to be scanned omnidirectionally. Mr. Woodland did not join our department at IBM Raleigh until our concepts were well on their way through development, and none of the claims or innovations in his and Mr. Silver’s earlier 1949 bar-code patent were incorporated in our scanner or symbol design.
I, George J. Laurer, invented the elegant UPC symbol, the EAN symbol, and the trailer designed for the publishing industry. I also hold several patents pertaining to modern-day scanners. In 1973 my contribution was recognized by IBM when I was presented with a corporate-level Outstanding Innovation Award and a significant monetary award.
George J. Laurer
The photo of ten Navy blimps on the cover of your Summer issue brought back memories. I witnessed this unique formation flight—which took place, I was told, for publicity purposes—in 1943 at the naval air station at Moffett Field, south of San Francisco. I was at the time a young research engineer at the government’s new Ames Aeronautical Laboratory, located at Moffett. As we watched from our office window, my colleague Max Heaslet remarked, “Now I know how it feels to live in the bottom of a goldfish bowl.”
Walter G. Vincenti
Department of Aeronautics and
In your article “Lighter Than Air,” by Peter Andrews (Summer 1993), I must question the caption on the bottom of page 16. The Los Angeles could not “draw a reconnaissance plane into its cavernous interior.” The Akron and Macon had hangars, but the smaller Los Angeles did not. The Los Angeles was furnished with an experimental device for hooking airplanes, known popularly as a trapeze, but its cavernous interior was filled with gasbags.
Also, on page 14, mention is made of the Shenandoah ’s “ballonets, used to maintain a constant pressure within the ship’s envelope.” As a rigid airship, it had no need of ballonets, which are used only in pressure airships, or blimps. And on page 21 the author refers to the Macon ’s “sophisticated radar equipment.” Surely the Macon had radio and radio direction-finding for its scout planes, but I do not think it had airborne radar in 1935.
Arthur D. Tenenholtz
Brooklyn, N. Y.
Peter Andrews notes that most rigid dirigibles met violent ends. Many of these losses reflected wartime combat and hydrogen fire. Yet even so, one finds that 37 of a total of 162 rigid dirigibles were lost through structural failure, in bad weather, and even in moderately strong winds during ground handling.
In the course of its career, the rigid dirigible racked up some 80,000 flying hours, no more than a modern airline accumulates in a few weeks. If such an airline sustained 37 major accidents during that time, many with loss of life, we would not have a commercial aviation industry. And widespread use of helium in dirigibles would have made things even worse. Because it has less lifting power than hydrogen, it would have brought oversize dirigibles having particularly lightweight construction. These would have been even more prone to structural breakup.
T. A. Heppenheimer
Fountain Valley, Calif.
Matthew Nicholl’s reference to the Theremin (“Good Vibrations,” Spring 1993) brings to mind that RCA attempted to introduce this device to popular music shortly after its commercial introduction in 1929. In April 1930 Victor released “I’m a Dreamer, Aren’t We All?” and “Love (Your Spell Is Everywhere),” with the Victor Theremin played by Zinaida Hanenfeldt. Evidently sales of this record were less than hoped for. Although it was still available in the February 1932 list, it was no longer included in the 1933 general catalogue.
Allen G. Debus
Morris Fishbein Professor of the
History of Science and Medicine
University of Chicago
On page 48 of “The Wrong Track” (Spring 1993), when it says “too much of the current was lost to resistance,” I envision a circuit wherein the current is not equal throughout. That assertion won me a steak dinner when I challenged it several years ago. The fact is that current is the same throughout the circuit and is neither lost nor consumed in resistance. Power is lost and energy is consumed, but current is the same throughout the circuit.
Angela J. Polvere