|Is Stackable?||Yes to 40|
Description (From Recipaedia )
Thermometer displays ambient temperature. It is an important tool when planting trees. Oaks like it warm, birches moderately cool and spruces cold. Planting a tree in a wrong ambient temperature will cause the sapling to wilt. It is also an electric element that outputs analog signal corresponding to the surrounding temperature.
You can carry the thermometer in your pack or in the hotbar and just look at it when you want to check the temperature.
The temperature value is indicated by the dots on the left. The bottom dot indicates a 'value' of 2. The next one is 5, then 8, 11 and 14.
The thermometer is used to indicate which species of tree to plant in an area. Spruce trees like it best around 1.5, Birch at 7.5 and Oaks like it the hottest at 10.
It can help you tell if you need to wear insulating clothing.
You can connect the thermometer to an electric circuit and it will output an analog signal proportional to the temperature:
The maximum temperature readout of 'F' is the heat of a block next to a fire block.
Some biomes may have a temperature less than '0' on the thermometer.
There is a bug since version 1.26 where the Thermometer does not register 'unnatural' heat sources when held. If you build a fire, its heat will not show on the Thermometer unless you place it on a wall.