In the mid-1800s, before gas and electric powered refrigerators, natural ice was cut from rivers and ponds and shipped into New York City to preserve food and cool drinks in homes, restaurants and for use in other commercial purposes. In the 1880s, 1.5 million tons of ice were sold in NYC from distribution ice houses across the City. Knickerbocker Ice Company dominated the New York market. One of their several ice houses was in Red Hook at the foot of Smith Street where ice could come in by barge.
One of the important uses of ice was in the manufacture of ice cream which was served in "ice cream saloons."
For more on the ice industry in Brooklyn see:
The Brooklyn Historical Society's Photo of the Week: Ice In Brooklyn
Wendy Elizabeth Harris And Arnold Pickman's paper:
Slip - Slidin Away: Archaeology and the Reconstuction of the Hudson River Ice Industry