266 Transactions. — Botany . 



I kept the juice in the evaporator constantly boiling till I found the 

 thermometer indicate 220° F. as the boiling-point. The temperature, 

 however, must have been much higher, as the original boiling-point of the 

 juice indicated only 210°, and I subsequently found that my thermometers 

 could not be relied upon at those high temperatures. As soon as 220° was 

 indicated I drew the fire, but the syrup, which had then thickened very 

 rapidly, continued for a long time in a state of ebullition. All the time of 

 evaporating I kept the juice stirred with wooden paddles to prevent burning, 

 but, in spite of all my care, a portion of the syrup got burnt. As soon as 

 possible I ladled out the syrup, which was now of the consistence of thick 

 treacle, into a 25-gallon cask, and found that I had about 10 gallons of syrup 

 of a rich brown colour. The cask I placed in a room with a fire to keep 

 the temperature up to 80°, the atmospheric temperature being only 66°. 

 Next morning I found one of the hoops had slipped, and treacle was oozing 

 through between some of the staves. For several days the heat was kept 

 up to 80° to 84°, but, there being no sign of crystallization, I drew off the 

 treacle, of which there were about 5 gallons, the remainder seeming to be 

 a yellowish treacle in a frothy condition. I have since been informed that 

 this was saccharate of lime. 



On the 10th April I tried a second experiment with the balance of Mr. 

 Banks' cane supplemented by sufficient of my own to make up a ton. This 

 we crushed at the rate of 21 gallons per hour. The fresh juice weighed 

 11-5 lbs. per gallon, showing a density of 12 at a temperature of 68° F. 

 Obtained 80 gallons of juice from the ton, but, in the boiling, just after 

 adding the lime, the whole thing suddenly boiled over and was destroyed. 

 The cause I cannot tell, unless it may be connected with the state of the 

 juice from Mr. Banks' cane, which had lain exposed to heavy rain for 

 three days. 



On the 11th I again crushed a ton of cane. This was of my own grow- 

 ing, fresh cut, and much riper than the former cane used. From it I 

 obtained 78 gallons of juice, showing a density of 13-5 at a temperature of 

 62° F. This I boiled as before, but on this occasion used pure shell lime, 

 which gave a much better result in clearing the juice, so that, when it came 

 into the evaporator, it was a light amber colour. Added sulphurous acid as 

 before to neutralize excess of lime, and continued evaporating carefully to 

 avoid burning until the syrup had obtained, as I thought, a sufficient 

 density — as I could not trust my thermometers. When it cooled, however, 

 I found it had not been sufficiently evaporated, so that on this occasion 

 also I failed to produce a cry stalliz able syrup. My public duties pre- 

 vented my further experimenting during the past season. I may here 

 mention, however, that Mr. Skey, the Government Analyist, in the month 



