ST. LOUIS • The 1904 World's Fair in Forest Park helped make the ice cream cone famous. It also introduced to a mass audience another cooling sensation that, oddly, never got much press.
The Missouri State Building, the host state's own exhibition hall, had a large air-conditioning machine in the basement that cooled most of its rooms. The machine operated much like today's central air-conditioning system in a typical American home — a system that has made oppressive heat such as we've seen this year much more bearable.
"That was the first time great numbers of ordinary people were exposed to the comfort of air conditioning," said Bernard Nagengast of Sidney, Ohio.
Nagengast, an engineering consultant, said he had studied the history of refrigeration and air conditioning for four decades. He described the contribution of the World's Fair to interior comfort in an article in 1999 for the ASHRAE Journal, a publication of the American Society of Heating, Refrigerating and Air-conditioning Engineers in Atlanta.
His evidence is from the pages of an old trade publication, called Ice and Refrigeration, that discussed and explained the system in 1904. "That's the only detail I have ever been able to find," he said.
By 1904, mechanical refrigeration was an established, if exotic, technology. The Lemp and Anheuser-Busch breweries were making their own ice by the 1880s. At the century's turn, commercial ice-making factories were common in larger cities. Anybody who worked in one of those plants, or who could sneak inside, knew the relief of artificially cooled air — especially in a place such as St. Louis.
But there is little in the local historical record about the fair's contribution to air conditioning. The Missouri History Museum, repository of much information on the fair, has only a few fleeting references in its files. An online search turns up occasional one-sentence references, and they seem to be quoting each other.
David R. Francis, the former mayor and governor who was president of the fair, published a two-volume official record of its machinery and other items of interest. He described in detail the output of the fairground's own ice-making factory. If he mentioned the air-conditioning system in the Missouri hall, it didn't rate a place in the index or table of contents.
But an official book of photographs from the fair did note the cooling system, saying of the Missouri building, "A refrigeration plant installed in the basement has the capacity to reduce the temperature in the building to 70 degrees even when the mercury may be in the 90s outside."
Ice and Refrigeration magazine said electric motors powered the compressor and the blower system's main fan, which was 7 feet in diameter. The refrigerant was ammonia, which still is used in some large commercial-refrigeration systems. It cooled all of the rooms in the two-story building except the library and lavatories. United Iron Works Co. of Springfield, Mo., installed the machinery.
"Visitors, not aware that the building was artificially cooled, were struck with wonder and were unable to account for the very perceptible change felt in the temperatures," said Ice and Refrigeration in its November 1904 edition.
The Missouri building was on Government Hill, near the site of today's World's Fair Pavilion. The building was destroyed by fire on Nov. 19, 1904, two weeks before the fair closed.
Nagengast said one reason why the Missouri building wasn't more prominent in history might be that other air conditioners already had been installed in private settings. In 1902, the New York Stock Exchange and a printing plant in Brooklyn became air-conditioned.
Nagengast said some movie theaters and hotels were air-conditioned in 1917, and the first window air conditioners were sold in 1938. Air conditioning in private residences, at least in America's steamy regions, became widespread by the 1970s.