Before modern medicines were developed, the recommended cure for tuberculosis (and other chronic diseases) was fresh air, rest, and sunshine. Sanatoriums sprung up to accommodate patients and serve their needs. Limair Sanatorium was one such facility, with a difference: air conditioning, provided by air pumped up from Virginia's famous Luray Caverns. It was the culmination of years of work by heating and ventilation engineer T.C. Northcott.
The Luray Caverns had been discovered and opened to the public for tours some 22 years before, but by the time Northcott leased them in early 1901, mismanagement had landed the owners in a heap of financial problems. According to resident historian and spokesperson Bill Huffman, these conditions likely contributed to Northcott’s ability to construct Limair, which entailed drilling into the caverns to access “lime air” that he believed had been disinfected by passing through miles of limestone chambers. “Otherwise, it probably wouldn’t have happened,” Huffman says.
“Mr. Northcott… has devoted many years to the problem of establishing an institution that would combine the advantages of sunlight and beautiful surroundings with an air supply at once voluminous and pure,” wrote Dr. Guy L. Hunner, a surgeon at the John Hopkins University Medical School. Hunner first visited Northcott’s Limair Sanatorium while vacationing in the Shenandoah Valley in 1901. “After investigating the caves of New York, Ohio, and Virginia, he secured building and park privileges over the Luray Caverns as a site comprising the greatest number of healthful and attractive features.”
Not only was the air cool, it contained fewer bacterial colonies than anywhere tested above ground. And the air in the building was completely replaced every five minutes. Read about Limair, an engineering marvel, at Atlas Obscura.