The building that burned on West Carson Street last week illuminated more than the night sky. It's also shedding light on a little known and long-forgotten piece of the city's industrial past -- the wholesale grain businesses that supplied the region's feed stores, farms, breweries and distilleries.

From the outside, the four-story, red brick warehouse wasn't much to look at; it was built in 1928 as a strictly utilitarian structure, with no exterior (or, for that matter, interior) ornament.

In a way, it's surprising that the building still existed, and not just because it's a relic of an era when the region supported far more farms and breweries than it does today. If the Port Authority's West Busway project had followed its original plan, the warehouse and its adjacent grain elevators would have been razed and replaced by a transit station by now. The station project was scrapped, but not before it triggered a mandatory historic resources review that resulted in a HAER report -- an investigation, for the Historic American Engineering Record, of the buildings and grain businesses they housed.

The report, by archaeologist Christine Davis and historian Frank Kurtik for Christine Davis Consultants of Verona, is a revelation not only for what happened there more than a century ago, but also for what was still going on when they visited in 1995. Who would have known, driving by, that there was a hive of activity in buildings that seemed nothing more than fortress-like storage towers?

David Glenn Stewart, born here in 1839, founded the D.G. Stewart Elevator and Feed Mill in 1873, when he was about 34. The son of William and Eliza Glenn Stewart, David, after finishing private school in Sewickley, became a clerk on a boat owned by his brother James, which ran between Mobile and Montgomery, Ala. Three years later, according to an encyclopedia of biography, David became a clerk with the War Department in Washington, D.C., where he remained during the Civil War. When it was over he traveled throughout the South with the U.S. paymaster, paying off Union regiments as they disbanded. He then spent a year visiting historic sites in Europe.

How Mr. Stewart became interested in the grain business isn't recorded, but in 1876, he built on West Carson Street a wooden grain elevator that could hold 50,000 bushels of grain, delivered via a siding from the Panhandle Division of the Pennsylvania Railroad.

The land on which the elevator was built was owned by Singer, Nimick & Co., whose riverfront Sheffield Steel Works was just across West Carson Street; Mr. Stewart married Jennie L. Nimick four years later.

The 1876 elevator was replaced in the 1880s by a much larger iron-clad timber one. Called the Iron City Grain Elevator, it had a capacity of 300,000 bushels of grain and was illuminated by lard-oil torches. Fire was an ever-present fear, one that was realized in 1911 when it destroyed the grain elevator.

Two years later, the company -- then called D.G. Stewart and Geidel after a 1906 partnership -- built Pittsburgh's first concrete grain elevator on the site of the burned one, using reinforced concrete for walls and interior columns. It was fireproof (and proved it last week) but only a third the size of the 1880s elevator, with less than half its capacity, holding 130,000 bushels.

By the 1910s, David Stewart was in his 70s with no heir apparent for his business. The Stewarts, who lived in a frame house in Morewood Heights above Sunnyledge, had only one child, Glenn, a Yale grad who was in the diplomatic corps for a few years in the 1910s before embarking on a globe-trotting and, by all accounts, eccentric and luxurious life. Marrying well twice, he was not one to be tied to the family business in smoky old Pittsburgh.

In or around 1919, Stewart and Geidel sold their company to the Jesse C. Stewart Co., which may have begun as a Pittsburgh branch of the Midwest-based George C. Christian feed company. As early as 1898, it appears, Mr. Christian's company had operated a wholesale grain business in Shadyside, in a building that still stands next to the former Pennsylvania Railroad tracks on South Aiken Avenue.

The HAER report was unable to find a family relationship between David G. Stewart and Jesse C. Stewart, an Ohio native who'd worked as a flour salesman before coming here as Christian's agent. My research didn't turn up anything either, except that Jesse's father, Franklin, was born in Pennsylvania, so there may be blood ties yet to be discovered.

The South Side location continued as a small single elevator, processing two to four railroad cars of corn, wheat, oats, rye and barley each day until the end of World War II. In 1945, Stewart built another elevator, this one with a 100,000-bushel capacity, adjacent to the 1913 one.

Both of the white-painted grain elevators still stand side by side, one emblazoned near the top with a large "S" for Stewart. The HAER report is detailed in its description of their equipment and workings.

Grain was cleaned, then moved to storage bins. There were bins for corn, oats, wheat, soybeans, middlings, distiller's grain, linseed and brewer's grain; they also provided cultivated grain for race-horse feed. On four floors the grains and feeds passed through mills, grinders, mixers, graders, sifters and conveyors. Grain was bagged (bags were sewn on site) and loaded onto Stewart's slat-sided trucks for delivery.

You can find the HAER report online, and see Bill Metzger and Charles Martin's photographs of the building interiors, by typing the phrase "HABS/HAER/HALS: Titles: 326" into Google or another Internet search engine.

The company's records, now at the Sen. John Heinz History Center, indicate the Stewart company was sold in 1954 to William Rose, whose descendants continued to operate the business at least into the 1990s. The last known address for the company, which appears to be defunct, was in Mt. Lebanon.

A century ago there were three grain elevators in Pittsburgh; today the Stewart elevators are the only surviving ones. The buildings were sold in 2008 to the Forza Group, which is considering building a hotel there.

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