Correction of temperature for radiation

In the above expression AT or AT is taken with + sign when the temperature is falling, and with — sign when the temperature is rising. All temperature readings are supposed to be made at intervals of one minute. For example— 

Number of mmutet from first reading. Temperature. AT 

Number of minutes from first reading. Tempttature. AT  

Having determined the water-equivalent of the apparatus, the heat of combustion of a substance (say, camphor or naphthalene) can be determined. The determination is carried out exactly in the manner described above. 

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