32 



REPORT 1865. 



superphosphate, guano-superphosphate, sulphate of ammonia, and ground bones, 

 taken singly or mingled together in definite proportions. The manures were 

 analyzed so as to be certain of their exact composition. In each set of experiments 

 the various operations were conducted on the same day with the plots of ground 

 allotted to each manure. The soils on which the experiments were made were in 

 part of a heavy nature, and in other parts of a light character — the proportion of 

 each being equal. Each experiment was conducted on a quarter of an acre, and 

 the twelve experiments consequently required three acres on each farm. The crop 

 was turnips, and the yield or produce was weighed on the field. The results 

 obtained were various on the different farms, as the manures which gave the largest 

 returns on one farm did not yield the largest crop on another. These variations 

 are to be expected in all field experiments, and are due to the special circumstances 

 or conditions of each field where the trials are made. "Where only one set of ex- 

 periments are conducted on a single farm, the local influences may materially affect 

 the results ; but where, as in the present case, the field operations are conducted on 

 ten farms, and the mean produce of the ten trials is obtained, then the disturbing- 

 influences of one farm are counteracted or practically neutralized by those of the 

 other farms. 



The full extent of the differences in the yield of the various manurial mixtures 

 may be more readily comprehended from the following Table, which gives the 

 manures in the order of their fertilizing powers according to the mean of all the 

 experiments : — 



Manure for Quarter of an Imperial Acre. 



Average produce 

 per Imp. Acre. 



Calculated from 



the mean money 



value (8*. 5d.) of 



each lot or manurial 



mixture. 



9 Stones 35 p. c. Guano Superphosphate 



5 Stones Peruvian Guano 



9 Stones 85 p. c. Bone-ash Superphosphate 



8 Stones 35 p. c. Bone-ash Superphosphate .... I 

 1 Stone Peruvian Guano f 



4 Stones 35 p. c. Bone-ash Superphosphate ... 



5 Stones Ground Bones 



8 Stones Phosphatic Guano 



1 Stone Sulphate of Ammonia 



6 Stones 35 p. c. Bone-ash Superphosphate . . . . j 



2 Stones Bolivian Guano [• 



1 Stone Sulphate of Ammonia | 



8 Stones 35 p. c. Bone-ash Superphosphate . . . 



1 Stone Sulphate of Ammonia 



7 Stones 35 p. c. Bone-ash Superphosphate . . . 



2 Stones Peruvian Guano 



9 Stones Phosphatic Guano 



6 Stones 35 p. c. Bone-ash Superphosphate . . . . ) 



3 Stones Peruvian Guano j 



6 Stones Phospho-Guano 



In Bulbs. 



Tons. cwt. qr. lb. 



21 12 2 19 



21 12 2 



20 14 1 8 



20 1 3 



20 18 



19 2 26 



18 8 3 16 



18 8 2 23 



It will thus be observed that, taking the mean produce from the ten trials, cal- 

 culated to the same money value for each of the manures, the greatest return of 

 crop was yielded by the dissolved phosphatic guano, followed closely by the Peru- 

 vian guano. Indeed the difference in the produce obtained from the plots treated 

 with these manures was so slight — only 19 lbs. to the acre— that they may be re- 



