“ Three canal commissioners shall be chosen at the general election which shall be held next after the adoption of this Constitution, one of whom shall hold his office for one year, one for two years, and one for three years. The commissioners of the canal fund shall meet at the capitol on the first Monday of January next after such election, and determine by lot which of said commissioners shall hold his office for one year, which for two, and which for three years; and there shall be elected annually, thereafter, one canal commissioner, who shall hold his office for three years. ”