120 



MANUFACTURE OF SUGAR. 



same principle to a rectangular flat bottomed pan, the fire 

 being allowed only to come in contact with the bottom. 

 Dr. Mitchell describes one of this sort as follows : — " One 

 of the most efficient articles of this kind I saw, was a large 

 iron rectangular pan, made by Crossley. It cost £25 

 sterling, including furnace mouth and bars. Its dimen- 

 sions were 6| by 6 feet, 18 inches deep at the sides, by 

 22 in the centre, the bottom being slightly concave, to 

 facilitate the exit of the contents through a large cock. 

 The drum, made of white pine for the sake of lightness, 

 had every second bar bucket shaped, to take up a greater 

 volume of syrup. Its dimensions were such, that the lower 

 portion of the circumference, suspended in the syrup, 

 dipped down to within two inches of the bottom of the pan. 

 The wheel on the axletree had eighty teeth, and the 

 driving pinion seven teeth; made two turns in fifty seconds, 

 and receiving the syrup (marking 220° F.) when hot, 

 turned out 180 gallons liquid sugar in seventy-five minutes, 

 at a temperature of from 164° to 170° F. The coal used 

 was 175 lbs. Time and fuel would be saved by using 

 Hague^s, or any other insufflator, for driving across the 

 pan, while in action, a current of dry air. The method is 

 decidedly good, and when well managed, will prove a 

 formidable rival to the vacuum pan. Its efficacy is more 

 than equal, probably, to any work that may be required in 

 this country (Trinidad). In working the pan, care must 

 be taken to give the proper speed, and to charge only a 

 few gallons at a time, and that only when the syrup has 



