Suppiemeni to '' Nature,'' June 24, 1922 



111 



EvQry \}d<rizty of 



Bigh 

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HLTER^ERS 



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Use WHATMAN FILTER PAPERS 

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 you. 



Samples, Price List and Booklet, giving full particulars 

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Callender & Barnes' Continuous Flow Calorimeter 



For the accurate determination of the electrical equivalent of heat. 



A stream of water is made to flow 

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 is heated by a manganin wire con- 

 tained in the tube and carrying a 

 known current. The rise in the 

 temperature of the water is measured 

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 the energy dissipated by the wire and 

 the volume of water passing per 

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 accurated to 1 in 400 are easily 

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The rate of flow of the water is 

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Complete with Cistern on stand and with two Thermometers reading 1/5° C. 



£4 4 



A copy of our 1922 catalogue No. 150 will he sent upon request. 



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