68 A Solution of the Sewage Problem. [January, 



per acre — it was superior to most manures in the market. 

 Moreover, an examination of the books of the Company 

 shows that the good opinion of agriculturists was genuine, 

 inasmuch as a man who, the first year, would grudgingly 

 take i ton as an experiment, the next year took iotons, and 

 the third year would increase his order to 20, 50, and even 

 100 tons, grumbling that the limited supply prevented him 

 having all he wanted. 



But it must not be imagined that the results of the la- 

 boratory and of practice are altogether anomalous in the case 

 of the native guano manure ; there is simply a difference in 

 degree, and this difference arises from the non-existence of a 

 fixed chemical standard of manurial worth. Nor does chemical 

 analysis always show a low money value for " native guano." 

 Samples submitted, at the Paris works, to one of the first 

 analytical chemists in France (M. Terreil, Aide-Naturaliste 

 en Chef des Travaux Chimiques au Museum d'Histoire 

 Naturelle) are reported by him to be worth in their dry state 

 108*6 francs per ton, or, when reduced by the normal amount 

 of moisture present in " native guano," and converted into 

 English money, £3 12s. 5d. per ton, whilst the cost of pro- 

 duction is far below that figure. 



As more particular evidence of the manurial worth of the 

 guano, we may refer to the results obtained on the experi- 

 mental farm of 7 acres established in connection with the 

 works at Crossness. The farm, as is indeed the entire 

 system, has lately been under the supervision of the Metro- 

 politan Board of Works. The following are the returns 

 from 9 yards square : — 



Golden Drop Wheat. 



lbs. ozs. 



. Native Guano, 15 cwts. per acre . . 6 4^ 

 Do. do. 10 do. do. . . 6 i.J 

 No Guano 2 14 



White Rough Chaff Wheat. 



lbs. ozs. 



Native Guano, 15 cwts. per acre ..67 



Do. do. 10 do. do. . . 5 7 



No Guano 5 4 



Revet Wheat. 



lbs. ozs. 



Native Guano, 15 cwts. per acre ..no 



Do. do. 10 do. do. . 10 14 



. No Guano. . ..68 



