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XV. — Report of Experiments upon Wheat, Barley, and Stvedes, 
undertaken by Members of the Cirencester Chamber of Agricul- 
ture. By John Weightson, F.C.S., Professor of Agriculture 
in the Rojal Agricultural College, Cirencester. 
Introduction. 
In conducting agricultural experiments tlie investigator is beset 
witli many difficulties, which tend to render his results indis- 
tinct, and to detract from the value of his work. Among these 
difficulties may be named the following: — (1) Inequalities in 
the condition or in the natural fertility of the soil ; (2) inequali- 
ties in the vigour of the plant ; (3) peculiarities of season ; and 
(4) attacks of insects. A number of plots may be measured 
off and treated with care, but, as the crop advances towards 
maturity, one or other of the above-named sources of error 
appears, causing differences not attributable to methods of culti- 
vation, or special dressings of manure. Hence the importance 
of repetition and control : for although a single series of experi- 
ments may yield results of comparatively small value, several 
series, designed with a view to confirm or control each other, 
will probably elicit evidence of almost irresistible strength. 
The Cirencester Chamber of Agriculture, in undertaking the 
work of conducting field experiments, kept this truth steadily 
in view ; and it will be observed that the variety of manures or 
methods of cultivation used was restricted. The treatment decided 
(upon was repeated sufficiently often to justify some useful con- 
clusions being drawn ; but, in spite of the precautions taken, 
contradictory results were occasionally obtained. Such dis- 
agreements are not uninstructive. They teach the importance of 
each farmer conducting experiments upon his own land in order 
to find its peculiarities. When a general concurrence of evi- 
dence is obtained, an important point is gained ; when dissimilar 
answers are the result, some special reason for the want of con- 
formity must be looked for in the soil and surrounding conditions. 
In the autumn of 1868, the Committee of the Cirencester 
Chamber decided to carry out a series of wheat-experiments. 
In planning this series it was resolved — (1) that the trials should 
be of a simple character ; (2) that the same series should be 
simultaneously carried out upon as many farms as possible ; 
(3) that duplicate plots should in every case be used. It was 
also determined that the experiments should consist of two series- — 
one a comparative trial between manurial substances, and the 
other between two or more methods of cultivation. Subsequently, 
experiments upon barley and roots were instituted. The fol- 
YOL. VI. — S.S. Y 
