America’s Strength

As a footnote to Arthur Molella’s fascinating interview with Thomas Hughes (“America’s Golden Age,” Spring/Summer 1989), one might cite the reaction of a Russian visitor to the America of President James Buchanan: “Young, active, practical, happy in their enterprises, the American people … will have an influence on Europe but they will use neither arms nor sword nor fire, nor death and destruction. They will spread their influence by the strength of their inventions, their trade, and their industry. And this influence will be more durable than any conquest.”

Recent geopolitical developments give reason to hope this optimistic prediction may yet turn out to be more right than wrong.

A. C. Hall
Dallas, Tex.

The Superconductor Scramble

I found John P. McKelvey’s article “Understanding Superconductivity” (Spring/Summer 1989) interesting and timely. Most of his comments and observations would fit perfectly into an article titled “Understanding Cold Fusion.” Among them: “the theorists are scrambling to put together the pieces thrown their way by experimentalists” “the increasingly interdisciplinary character of the research has created serious problems of communication” “a race is on, and the pace is very fast” and “if you only read the scientific journals, you will be hopelessly behind the times.” Can history be repeating itself in so short a time?

W. R. Hansen
Salt Lake City, Utah

The Superconductor Scramble

I found “Understanding Superconductivity” fascinating, but one part of it completely mystifies me. I refer to the statement that “since opposite magnetic poles repel each other, a strong repulsive force arises between the perfect conductor and an external magnet.” If this is indeed true, it refutes the basic law of bipolar magnetism, that opposite poles attract and like poles repel each other.

Robert N. Pfeffer
Leslie, Mo.

John P. McKelvey replies: I am indebted to Mr. Pfeffer for pointing out that misstatement, and I hasten to assure him that, having taught electricity and magnetism for twenty-seven years, I do understand that opposite magnetic poles attract. However, there are physically really no such things as magnetic poles; the effects we ascribe to them actually arise from circulating currents of charged particles or the intrinsic magnetic fields of atoms. That is why when you break a bar magnet in half you get two similar bar magnets, each with a north and south pole, rather than an isolated north pole and an isolated south pole. Each atom of the permanently magnetized substance, in fact, has its own north and south pole and is surrounded by a magnetic field like that of an electric circuit around which a current flows. So people tend nowadays to speak of the interaction of currents rather than of magnetic poles. It turns out that parallel currents flowing in the same direction attract each other, while oppositely directed parallel currents repel. This is the source of my misstatement. What I meant to say, and should have written, was “Since opposite currents repel each other, a strong repulsive force arises. …”

The Life Of Lear

Your articles on Chester Carlson (“Struggling to Become an Inventor,” by Dean J. Golembeski, Winter 1989) and William Lear (“King Lear,” by T. A. Heppenheimer, Spring/Summer 1989) leave me just a little cold, both as a human being and as an engineer. It’s hard to imagine how the world got along before the days of quick, easy xerography, and modern aviation would surely be on a much smaller scale without autopilots. But both men were wealthy, unhappy, and insecure.

When entering the engineering field, I vowed that my career would never supplant my family and personal well-being. That vow is regularly challenged as the responsibilities of daily business press on. I cannot consider a person’s life a success if he has failed his family. Having world-changing success does not alter that opinion. Neither does philanthropy. That may sound harsh, but no society can survive if it concentrates on career accomplishments and ignores personal responsibility. Technology cannot raise children, nor can it save marriages.

Tim Larson
Lemon Grove, Calif.

The Life Of Lear

I have known neither Mr. Heppenheimer nor the late Mr. Lear. I do know of many of Lear’s contributions to American and international industry and found the article on him insulting to his memory and achievements. I suggest in the future your editors hew to the lofty title of your publication and leave the pop-psy and titillation of Mr. Heppenheimer’s writing to the sort of papers and magazines offered at supermarket checkout counters.

T. O. Thompson
Severna Park, Md.

The Life Of Lear

We read with interest the story entitled “King Lear” in your Spring/Summer issue. The article is excellent.

William G. Robinson
Vice President, Corporate Affairs
Learjet Corporation
Wichita, Kans.