From Barn Plans and Outbuildings, , Chapter 13, p 170, New York, O. Judd Co., 1886
"The main points to look at in constructing a springhouse are, coolness of water, purity of air, the preservation of an even temperature during all seasons, and perfect drainage. ... The spring should be dug out and cleaned, and the sides built up with rough stone work. The top should be arched over or shaded from the sun. A spout from the spring carries the water into the house.
The openings which admit and discharge the water should be large enough to allow a free current of air to pass in and out. The openings are to be covered with wire gauze to prevent insects or vermin from entering the house.
The size will depend altogether on the number of cows in the dairy.