1 62 On Steam and Brines 



amounting in the extreme to O'2 F. All the observed tem- 

 peratures have been corrected accordingly. 



The General Order of the Experiment. The temperature 

 of saturated steam was determined in the straight steam tube. 

 The U-shaped receiver being clean and dry, was weighed. 

 The portion of salt, usually one-fifth of a gramme-molecule, 

 was weighed out carefully into the receiver, which was then 

 again weighed for the purpose of afterwards arriving at the 

 weight of the condensed steam. The weight of the receiver, 

 both empty and charged, includes that of the thermometer 

 and its attachment. When steam is issuing from the boiler 

 at the top of the T-tube, the receiver is connected with it, as 

 shown. The top of the T-tube is now closed with the cork, 

 and the passage of steam through the salt begins. The time 

 is noted when the steam reaches the salt, and this is the 

 beginning of the experiment, and the time is logged as a 

 part of every entry in the note-book. It is particularly 

 noted when the mass in the receiver forms a liquid magma 

 through which the steam bubbles, when the thermometer 

 attains its maximum, when it begins to be unsteady, and 

 when steam is shut off. Before reaching the maximum the 

 temperature is noted every half-minute, afterwards every 

 minute, and at the end every half or quarter-minute. When 

 it is judged by the fall of temperature and the quantity of 

 salt undissolved that these two small quantities compensate 

 each other, the cork is removed from the T-tube and the 

 operation is interrupted. The receiver is then quickly dis- 

 connected from the india-rubber tube, and suspended from 

 the scale, which is within arm's reach from the working bench, 

 and the weight ascertained to the nearest decigramme. The 

 receiver is then immediately reconnected with the boiler, the 

 cork inserted, and boiling recommenced. Steam is passed 

 until the temperature has fallen to the first attainable whole 

 number of degrees above the temperature of saturated steam, 

 when it is interrupted, the weight observed and the receiver 

 reconnected, to be again weighed when the next whole degree 

 is reached, and so on until so much water has collected in the 

 receiver that the steam can no longer be passed through it at 



