How Did One Keep Ice Icey in the Summer of 1845?

JF Ptak Science Books   Quick Post

 I cam upon this curious drawing in The American Agriculturalist for July 1845.  "Ice-House" it was, and the accompanying text described how this design was found to be among the most perfect. There is even a recommendation for the design from a gentleman in Virginia, a summertime recommendation from a moist and steamy environment. The author described how well the building worked, built into the side of a hill with a 12-foot-square pit dug 14' down, and how the bottom of the pit was never revealed, even after eight summers of ice and heat...there was always something cold down in the hole. 

I wonder how old the oldest ice was in the state of Virginia or any other hot place, how old the oldest unrefrigerated ice may have been? The thought would be that you would just need to keep adding ice, but that other ice needed to come from somewhere, and in 1845 that "somewhere" may have been nowhere at all--after all if the ice didn't melt then we would have a significant problem with the laws of the universe. 

And the full text, with descriptions on how to construct the ice house: 

 

[Click to expand.]