Where was Adam Smith's "invisible hand" in the present financial crisis? As an engineer observing the crisis in the U.S. financial system, I scratch my head when I read the reasons given for the meltdown of the housing market and even the banking system (i.e., Bear Stearns). I asked myself, where were the control regulations, the "servomechanisms," that should have prevented the acceptance of the loans in the first place? The relaxation of regulations that began during the Reagan administration is being felt today.

Technical people know that certain mathematical functions will become infinite unless a limit is placed on certain variables in the function. Engineers know that an electric motor of a so-called "squirrel cage" design can spin itself apart unless the motor wiring is designed to prevent (regulate) this phenomenon. The simplest feedback control of all is the lowly fuse or circuit-breaker that fuses or trips when a wire current exceeds a safe wire size. That's automatic feedback we all recognize and appreciate. I see others (e.g., columnist David Brooks, "We're All Bailout Artists Now," March 19) using the analogy.

I never liked the phrase "invisible hand," because I know that feedback control is always necessary to keep any system stable. Not having automatic control is like our pulling a wall plug after we see smoke. There is always a danger that too many of the factors that are operating on any system can randomly "decide" to move in the same direction at the same time. So much for the invisible hand.

I wonder if Congress will insert at least a fuse into the financial hydra. Maybe engineers should explain what automatic feedback control is.

THOMAS C. RUPPEL
Bethel Park

The writer is a retired engineer.

I appreciated the Feb. 26 editorial supporting the grass-roots effort to oppose Allegheny County Chief Executive Dan Onorato's move to take away Allegheny County control of our air, rivers and soil ("Clear the Air: The County Should Fix the Pollution Program").

Also, I do not think that research on nuclear energy and coal at the University of Pittsburgh will benefit this region. These systems are a major cause of carcinogenic and cardiovascular disease, profiting the global corporations that provide funds for institutes to support their greed.

Why don't we have safe, clean, community-run renewable energy systems that would keep us healthy and provide jobs and peace?

LIZ HUGHES
Vice Chair
Allegheny County Greens
Squirrel Hill

It was with great interest that I read the March 19 story regarding cloth diaper use ("Better for Baby?").

When my son, who is now nearly 19, was a baby, we turned to cloth diapers when he developed severe diaper rash from disposables. At the time, I was working full time during the day and attending nursing school in the evenings and on Saturdays. One would think having a baby in cloth diapers would just add another chore to the mix, but it was surprisingly low maintenance. I also had the good fortune to belong to a day-care center that supported the use of cloth diapers. I think I did a washload of diapers every five days or so, not a huge addition to my laundry day. It saved us a lot of money, even considering the initial investment in the diapers and the cost of washing them.

At some point, I also remember finding a mail-order source for washable diaper covers, a great alternative to pins and plastic pants. They were colorful, velcro-fastened covers that were lined with fluid-resistant material; one laid the folded cloth diaper inside and fastened it up in a similar fashion to a disposable diaper.

We used cloth on my daughter five years later as well, for the most part. I encourage all young mothers to at least try cloth diapers. Your baby's bottom will thank you for it, and so will the landfills!

JENIFER SZMYD
Glassport

In reference to recent letter writers who objected to Hillary Clinton marching in the St. Patrick's Day parade: Politicians have marched in the St. Patrick's Day parade forever. If your new god, Barack Obama, had marched, would you have sent in letters complaining? No, you would not.

Get real.

VIRGINIA SHEADER
Glassport

My compliments to letter writer Mary Ann Harsch ("The Race Card," March 19). I, too, am an older, highly educated white woman who is voting for Barack Obama.

Furthermore, I want to take this opportunity to express my concern that a vote for Hillary Clinton is a vote for John McCain. I strongly believe that if Mr. Obama isn't the Democratic candidate, then young voters and black voters will stay home in disgust. It will be too painful to see their candidate with the popular vote pushed aside for political reasons and they simply won't vote, making Mr. McCain the next president.

ADELE SILZ
Mt. Lebanon

Your editorial "The Speech" (March 19) clearly expressed the eloquence of Barack Obama's speech on race and division in America.

As a retired United Methodist pastor, I have often preached on the words of warning by the biblical prophets. Some used strong, angry words, i.e. Amos and John the Baptist. Others, like Isaiah, spoke using captivating, poetic images. Jeremiah Wright captures our attention, like a John the Baptist, with strong, angry words. Barack Obama, however, like Isaiah, offers an imaginative poetic picture of hope for understanding and reconciliation.

BARRY L. LEWIS
Aleppo

Thank you, Rosebud Fine Food Market and Deli, for taking a chance in opening a grocery store in Downtown Pittsburgh ("New Downtown Market a Hit With Early Customers," March 19).

I have lived in Downtown Pittsburgh for almost six years now, without a car, and it was a joy to walk several blocks from my apartment to your new store and purchase groceries. I wish you all the best and much success and promise to be a regular customer.

MILLICENT A. SMITH
Downtown

The March 13 Web article "HHS Official Urges Participation in Electronic Health Records Project" indicated that health-care leaders in Pittsburgh may not be aware of every available option for expediting the adoption of health information technology.

Specifically, a Pittsburgh Foundation program to award grants to doctors to pay for electronic health records systems was reportedly shelved due to concerns that it could violate federal tax and anti-kickback policies.

Health IT can not only save money but it can also save lives by eliminating errors and improving the quality of care. Recognizing that, in 2006 U.S. Department of Health and Human Services Secretary Mike Leavitt put in place rules allowing hospitals and insurers to help doctors go digital -- without running afoul of anti-kickback laws. Hospitals and other entities that adhere to the new rules can supply physicians with hardware, software and training services in lieu of cash grants, which are prohibited by federal tax and conflict-of-interest laws. The Internal Revenue Service has adopted similar rules.

While I don't know the details of the Pittsburgh Foundation initiative, these more flexible rules could very well allow some version of it to go forward.

THOMAS BARKER
Counselor for Health Policy
U.S. Department of Health and Human Services
Washington, D.C.

As of March 16, changes on the West Busway took effect. When the busway was being proposed, we were told that we would have some of the best service in the city. Apparently, this was meant only for the residents of Moon. This will be the third attempt I know of that gives these people preferred treatment.

Currently, the early morning stops in Crafton are at 5:27 a.m., 5:55 a.m. and 6:12 a.m. Each one of these buses will have people standing in the aisles to get into town. I may have never taken a bus scheduling management course in college, but common business sense 101 would tell me that adding another route, not reducing, should help boost ridership. Happy commuters equal more money. Maybe with better management, the Port Authority would not have to be bailed out by the people of Allegheny County.

On previous attempts to give the people of Moon their own express, these buses would pass us in Crafton with fewer than 10 people on board. My question would be, who lives in Moon with connections to the Port Authority?

JOHN MORLEY
Robinson

Could your newspaper be any more overtly pro-Barack Obama? From the selection and presentation of the campaign news and pictures to the political cartoons, columnists and letters to the editor, apparently Mr. Obama is faultless, irreproachable, almost the "second coming." Except for the mild William Kristol column last week ("Generation Obama?" March 18), nary a critical word about him can be found in your pages.

Meanwhile Hillary Clinton has been presented negatively overall: "The serpent of Eden," says one letter writer ("Time to Get Tough," March 17)? Please! And to compare her to unqualified wives who inherited their offices from their husbands is ridiculous. She is a smart, highly educated lawyer who won her office as an elected senator in spite of her husband's reputation and she has served admirably ever since.

This prayerful cry for "hope" in Mr. Obama's name seems nonsense to me. What we need is a common-sense practical leader with the courage to end our presence in Iraq and who can effect lowering our dependence on debt and on foreign fuels. Sen. Clinton's platform seems very good to me.

As Ben Franklin said, "He who lives upon hope will die fasting."

It's time for a more balanced news source.

A. STRAUB
Murrysville

I am a white, female, college graduate baby boomer and a big supporter of Barack Obama.

Much has been said of our Pennsylvania voters, none of it very flattering; even our own governor thinks we're too backward to look past a man's skin color, which means we're less progressive than most of the other states in our country. I've been driving with an "Obama 08" sign in my back window since November, and I can say I've not noticed another one until recently.

My girlfriend, my mom (who is 88) and I went to the St. Patrick's Day parade in Pittsburgh to march for Barack Obama with Mike Lamb and Franco Harris. We met with a nice-sized group of Obama supporters. I met a young woman, an unpaid volunteer, who drove seven hours from Michigan to be in the parade. There were others from as far away as South Carolina.

Just as the parade was starting we were told that we could not march in the parade -- that in spite of the governor, mayor and Hillary Clinton being in the parade, it was nonpolitical. We were told that Clinton supporters and their signs also would be banned from the parade. However, when Mrs. Clinton passed us by, she had her group surrounding her with signs and banners.

One woman complained to us that she came to see the parade and that our political signs for Barack Obama were blocking her view.

To her and others, let it be known that we would have preferred to have marched down the streets rather than be relegated to the sidewalks.

The two groups were in no danger of clashing, not that we would. It's just great to see the old-time dirty machine politics marched out in front of us and our young visitors from out of state. Pennsylvania, the place where hope goes to die.

JO ANN NELSON
Cranberry

March tolls the 130th anniversary of the Molly Maguires' executions mentioned in an engaging article from March 3, 2006: "Family Tries to Clear Miner's Name." In the 1800s, the Reading Railroad monopoly didn't pay miners enough to feed families. Unions were illegal, so the Irish "Molly Maguires" sabotaged mines. In 1877, the Reading Railroad prosecuted leaders of the Ancient Order of Hibernians, founded in Pittsburgh, on exaggerated murder charges. Juries lacked Irish and miners. Nearly all the jurors knew about the cases before the trials.

On March 25, 1878, railroad police supervised Patrick Hester's, Peter McHugh's and Patrick Tully's botched hangings. In 2006, Pennsylvania's Senate recognized that pro-railroad judges denied Hester a fair trial.

Now, state Reps. Anthony DeLuca, Dan Frankel, Harry Readshaw and Don Walko of Allegheny County and Joseph Petrarca of Westmoreland County are sponsors of House Resolution 629 to remind the governor to acknowledge the violation of due process.

May we remember Irish immigrants' struggle for liberty and survival this month.

HAL SMITH
Oakland

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