116 Southern's Experiments on the Density of Steam. 



If the whole number of strokes in each experiment be di- 

 vided by the number, found as above, that were required to 

 discharge one cubic foot of steam, the whole number of cubic 

 feet of steam discharged in each experiment will be given ; 

 viz. 5l54.4-13-164. = 391-53; 24.34-T-12-941 = 188-09 ; and 

 1599-i-12-724 = 125-66; the quantity of steam formed and 

 discharged in the first, second and third experiments respec- 

 tively, in cubic feet. 



If the weight of water gained by the condensation of steam 

 in each experiment be multiplied by 27-65, the number of 

 cubic inches of water in a pound weight, and divided by the 

 number of cubic feet of steam which were condensed, the 

 quotient will give the portion of water, in cubic inches, re- 

 quired by each cubic foot of steam for its formation; and hence 

 also the comparative density. 



Thus 20-25 X27-65-7-39] -53 = 1*430"] inches of water to 

 20-00 X 27-65-M88-09 = 2-940 ^ form each cubic 

 19-45 x27-65-=-125-66 = 4-279j foot of steam; 



r 40-001 

 and these numbers are proportional to< 82-24 >-the relative 



L119-70J 



densities, while the elasticities were as-< 80 > respectively. 



L120J 



These results appear to suppoi't the conclusion that the 

 density of steam is nearly, if not accurately, iwoportional to its 

 elasticity; at least this may be affirmed of it within the limits 

 of these experiments. 



From the above experiments may be calculated the latent 

 heat of steam developed in the three cases ; for if the weight 

 of the water which received the augment of heat, be multiplied 

 by the number of degrees of temperature communicated to it, 

 and if this product be divided by the accession of weight to 

 the water (which only could have communicated the acces- 

 sion of temperature), it is evident that the quotient will give 

 the temperature which the steam lost; and if to this be added 

 the temperature which it retained (viz. that of the water in 

 the cistern at the conclusion of the experiment), a number will 

 be obtained showing the isohole heat, or the sum of the latent 

 and sensible heat of the steam. Hence, by subtracting the 

 sensible heat of the steam from this sum, the latent heat will 



be found. That is, — '- — , ^ — |- col. 8 = the sum of the 

 col. 7 



latent and sensible heat ; or, 



