Ice

Ice is now mechanically produced on an large scale, but before appropriate coolants were developed ice was harvested from natural sources for human use.

Ice harvesting

Ice has long been valued as a means of cooling. Until recently, the Hungarian Parliament building used ice harvested in the winter from Lake Balaton for air conditioning. Icehouses were used to store ice formed in the winter, to make ice available all year long, and early refrigerators were known as iceboxes, because they had a block of ice in them. In many cities, it was not unusual to have a regular ice delivery service during the summer. For the first half of the 19th century, ice harvesting had become big business in America. Frederic Tudor, who became known as the “Ice King,” worked on developing better insulation products for the long distance shipment of ice, especially to the tropics. The advent of artificial refrigeration technology has since made delivery of ice obsolete.

In 400 BC Iran, Persian engineers had already mastered the technique of storing ice in the middle of summer in the desert. The ice was brought in during the winters from nearby mountains in bulk amounts, and stored in specially designed, naturally cooled refrigerators, called yakhchal (meaning ice storage). This was a large underground space (up to 5000 m³) that had thick walls (at least two meters at the base) made out of a special mortar called sārooj, composed of sand, clay, egg whites, lime, goat hair, and ash in specific proportions, and which was known to be resistant to heat transfer. This mixture was thought to be completely water impenetrable. The space often had access to a Qanat, and often contained a system of windcatchers which could easily bring temperatures inside the space down to frigid levels on summer days. The ice was then used to chill treats for royalty on such occasions.

Long time storage

People used to keep ice all summer from that which they harvested from clean sources at that time, it was lakes and streams...they had ice houses...sometime partially or all the way buried in the ground. They would cut the blocks big, as bigger lasted longer...then stack them all buried and covered up is LOTS of sawdust. When they wanted ice in the summer they would dig out a block, rinse off the saw dust and there you go.... That was the way commercial producers of ice also warehouse huge quantities of ice to sell in the cities to folks with ICE BOXES" the precursers to refrigerators. The great depression delayed everyone having refrigerators for awhile.....my grandmother had her old ice box in a shed when I was growing up.....it had a big old tin drip pan under neath that caught the melt water from the ice...It was an ongoing battle to keep the ice in the ice box and the drip pan emptied.