By 1892, Barre granite had become a premier stone for monuments, mausoleums, and gravestones. Pneumatic machinery was introduced to help meet the soaring demand.
Along with pneumatic machinery came dust, and with dust came silicosis, a debilitating and often fatal lung disease that plagued Barre granite cutters who worked in the manufacturing sheds during the first few decades of the 20th century, after the introduction of pneumatic equipment.
Doctors and laymen alike had long recognised dust as a problem for granite cutters and other dusty trades. But, ironically, a major medical breakthrough confounded the discussions about phthisis (lung disease) in granite cutters.
In the 1870s, the work of Louis Pasteur, of pasteurisation fame, brought microscopic bacteria and germs to the attention of the medical community. Robert Koch, a German physician, followed Pasteur’s lead, and in 1882 he discovered mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB).
Koch’s discovery led to almost universal agreement among the American medical profession that germs, not dust, caused phthisis. All cases of lung disease were then diagnosed as TB. Researchers mocked the theory of quartz lungs, and in the US the study of industrial causes of phthisis ceased.
Many granite cutters, including shed owners who worked alongside them, accepted the medical opinion that their illness was a form of TB caused by germs from unsanitary practices at work and home. Support for the biological cause of phthisis continued into the mid-1920s.
But beginning in 1912, British researchers published a series of papers documenting that non-infectious cases of phthisis could occur when TB was grafted onto a fibroid growth in the lung originally caused by dust. Unfortunately, many of their reports did not reach American researchers.
In 1922, the US Bureau of Labor Statistics (BLS) published a report that concluded phthisis from exposure to dust was distinct from TB, and was caused by the inhalation of minute particles of silica. Insurance company statisticians reported exposure to dust from silica-rich rocks such as granite produced a statistically significant predisposition to phthisis, whereas dust from limestone did not. The BLS admonished the medical community for focusing exclusively on bacteriological causes of phthisis and ignoring workplace-related causes.
Concurrently, DC Jarvis, a doctor practising in Barre, observed that granite cutters’ phthisis was not recognised by local doctors. He endeavoured to convince physicians and granite cutters that the disease was caused by work in a dusty environment, not from biological sources.
Meanwhile, the workforce of skilled stonecutters was greatly affected by the death of some of its most skilled and senior workers from silicosis. Those workers not only left the workforce prematurely but were unable to mentor apprentices. Immigration quotas passed in 1917, 1921 and 1924 greatly complicated the ability of shed owners to replenish the workforce with skilled stonecutters from Europe.
With a clearer understanding of the causes of stonecutters’ phthisis, and faced with a shortage of workers, shed owners looked in earnest for means to protect their workers from the harmful effects of dust. In the 1920s and 1930s they introduced dust control methods, including sweeping the floors, wearing masks and the installation of what turned out to be ineffective ventilation equipment in the sheds. More efficient dust control systems were developed, and during 1936 an agreement was reached that required all manufacturing sheds to install effective suction equipment on all dust-generating machines.
There have been no silicosis deaths amongst Vermont granite industry workers since 1940.