The new company combined the operations of 37 mining and calcining plants producing agricultural and construction plaster.

• Construction of gypsum calcining plant, Paris, Ontario.

• Construction of gypsum crushing and calcining plant, Hillsborough, New Brunswick.

• Operation of ochre drying and calcining plant (until 1889) at mouth of Petite Romaine River, Quebec.

The line was extended from the mill branch at Elephant Mountain to cross the Mojave River on a Pratt through truss bridge before pulling into the Columbia Mill on the other side of the river, where the calcining plants were located.