Hot water bottles are used for fomentation. This shows that water.

Fomentation: Fomentation is the ability of the material to give warmth to the body to reduce the pain by relaxing the skin.

Hot water bottles are used for fomentation:

• Water does not cool because of its high specific heat capacity and this specific property of water is exploited through the usage of warm water bottles.
• Also, in case you note the shape of a warm water bottle, you will realize that when water is poured inside the bottle there may be no way for even the water vapour to break out.
• The simplest way for the warmth to escape is by the surface of the water bottle.
• This whole isolation with the aid of using water bottle we could it to offer warm temperature for even greater time duration.

Therefore, hot water bottles are used for fomentation.