268 SEC. 8. HEAT. 



IV. C ALORIMETRY. 



1063a. Original Apparatus of M. Hegnault for ascer- 

 taining Specific Heat by observing Refrigeration. 



College of France, Paris. 



lO97a. Diagrams (3), representing the Apparatus of M. 

 Regnault, by M. d'Obelliane. Polytechnic School, Paris. 



1064. Lavoisier's original Calorimeter. 



Conservatoire des Arts et Metiers, Paris. 



Pabre and Silbermann's original Calorimeter, for 



measuring the heat disengaged in combustion. 



Conservatoire des Arts et Metiers, Paris. 



lO64a. Original Vessel, by Dulong, for measuring Specific 

 Heat by Refrigeration. Polytechnic School, Paris. 



1064b. Original Apparatus, by M. Hegnault, for ascer- 

 taining the latent Heat of Steam at diiferent pressures. 



College of France, Paris. 



1057. Apparatus employed by Dr. Andrews in his experiments 

 on the amount of heat disengaged in the combination of hydrogen 

 and other combustible gases with oxygen. Dr. Andrews, F.R.S. 



The gases contained in a cylindrical vessel of thin copper are exploded by 

 the ignition of a fine platinum wire, and the heat is measured by the rise of 

 temperature of the water in a calorimeter, capable of being rotated gently 

 round its horizontal axis. 



1058. Apparatus for determining the amount of heat produced 

 in the combination of liquids and solids with 'oxygen. 



Dr. Andrews, F.R.S. 



1058a. Fabre and Silbermann's Calorimeter. 



L. Golaz, Paris. 



This apparatus consists of:- 1. A large brass vessel closed by a cover in 

 two parts and open in the centre. 2. A thin copper vessel coated with silver 

 in the interior. 3. A vessel like the preceding, fitted with a cover. The 

 calorimeter is supported in the centre of the second enclosure. The space 

 between it and the second enclosure being lined with the skin of a swan. In 

 the interior of this vessel is placed an agitator and a thermometer, made with 

 great precision.' All these different enclosures are placed in a large and 

 solid triangular support, having two plates united by three copper columns. 



The combustion chamber is a thin copper vessel, having at its upper 

 extremity an opening closed by a plug flush with the side of the chamber, 

 and provided with a tube by which the gases and the products of the com- 

 bustion are discharged. A helix formed by a thin tube is fixed to this 

 opening, and so arranged that the gases pass through it from end to end, and 

 are discharged at the upper extremity, whence they are collected in vessels 

 placed for that purpose. A second tube is fixed to the combustion chamber 

 reaching to the lower part, and serves for introducing the oxygen into the 



