326 



EEPOKT OP THE COMMISSIONEPw OF AGRICULTURE. 



Analysis of Lake Parkinson and Potomac waters. 



[Grains per United States gallon of 231 cubic inches.] 



The sample of Potomac water was taken after a period of long- 

 continued drought, and was unusually clear and free from all clay 

 held in suspension. 



The Parkinson water contained so much organic matter, that it was 

 found impossible to estimate the free and albuminoid ammonia by, 

 the usual process, though a dilution of 1:1000 was tried. 



The presence of copper in the water is remarkable, and probably 

 exists in a state of combination with some organic acid. 



The strike-pan used was quite unsuitable for boiling to grain. Its 

 base was once the bottom of a much smaller pan, and a shelf several 

 inches deep had been added to support the enlarged top. All the 

 large steam-coils were above this shelf, and it took eight hours to 

 bring the contents of the pan above this point. We had no sugar- 

 boiler, but my assistant, Mr. G. L. Spencer, took charge of the pan 

 and did remarkably well; 



The sugar dried slowly in the centrifugals. These were not well 

 set, and could not be run at a very high speed on account of shaking. 



It took nearly forty-eight hours with three machines to dry the 

 sugar from the b3.25 tons. 



This dlLflculty in drying was due either — 



(1) To the process of diffusion; {%) to the process of carbonatation; 

 (3) to the fine grain produced in boiling; (4) or to the poor quality 

 of the cane. 



Which one oi these causes was most potent only future experi- 

 ments will decide, I am not wise enough to place it, as has all'eady 

 been done by some premature critics, on one of them alone. 



It seems most reasonable to suppose, however, that the poor qual- 

 ity of the cane and the extreme fineness of the crystals were the chief 

 causes of the difficulty mentioned. The process of carbonatation has 



