08/30/2026
Coboconk's Lime Kilns
In the second half of the nineteenth century, masonry construction became common in the Kawarthas and southern Ontario more generally—stone foundations, brick (veneer) and less commonly solid stone buildings. At that time, most buildings used lime as mortar, which was made by burning limestone in a kiln. At the end of the nineteenth century, Portland cement started to become common—the Peterborough and Kirkfield lift Locks were monuments demonstrating what could be done with concrete.
In 1889, Robert Callan (less commonly Callen) opened the Coboconk Lime Works, having previously made this product at St. Mary’s and Innerkip. He hired Scottish masons to come and build the kilns. Exporting the produce to Lindsay, Port Perry and Toronto, it soon became one of the community’s largest industries. Later operating as the Canada Lime Company and the Toronto Brick Lime Company, it remained a pillar of the local economy until the Great Depression.
To quarry the limestone, workers would drill holes in the rock, to place dynamite charges, which would blast the bedrock apart. The chunks were loaded in wheelbarrows, and shoved up the ramp into the kiln. Workers supplied firewood to fuel the fires, often burning round the clock at extremely high temperatures. After baking, the lime resembled white chalk, which was bagged, then loaded on carts to roll down the main street to the railway station. In Toronto, the lime was combined with clay to make Portland cement. Ben Farrow, who cut firewood for the kilns, recalled that there were up to 12 or 14 teams drawing wood to keep the fires blazing. 60 men worked in the quarry during the summer months. The surrounding sheds kept the firewood and lime dry.
Emma Windatt remembered how village children used to play with the lime. Sometimes when the lime cart was fully loaded, a piece or two would fall off as it made its way up the main street. Local kids would put the lime in a jar, add water, screw on the lid, then throw it in a pond. “There would be a big bubble in the pond, and the water would all turn milky as the jar exploded underwater. The fish would rise, belly-up to the surface, stunned by the explosion. After a time, that got to be boring and we wanted to see the explosion, so we would tie the jar to a willow branch and watch it explode. There would be glass flying all over.” The fun lasted until one child was struck with flying glass in the leg.
During the Great Depression, industries throughout the area were hit hard, as demand for many goods suddenly dropped. A competing kiln opened at Milton, and though locals said it was of inferior quality, it was closer to Toronto, and demand for Coboconk lime declined, forcing the kiln to close. “It was a disaster,” Emma explains. “So many people that had worked at nothing else, and had no other trade, were left without a job.” Nearly a century later, the old limestone kilns remain the landmark welcoming visitors from the south to Coboconk.
