191 1.] Summary of Agricultural Experiments. 145 
has now been carried on over three seasons with the object of ascertain- 
ing the amount of seed it is economical to use for a one year's ley. 
The. plots in each trial were seeded down in the barley crop of the 
preceding- year, and the produce of the plots was cut and made into 
hay before weighing. The mixtures consisted of Italian Rye Grass, 
Red Clover, Alsike, and Trefoil, and in some of them Cow Grass, 
Perennial Rye Grass, and White Clover were added. The amount and 
cost of the seed used and the resulting crops are shown below : — 
Avera ge 
crop, 
tons cwt. 
2 7 
2 5 
2 5 
2 7 
The heavy seedings have thus not given so good a return as the 
lighter seedings. Very little difference could be seen in the appear- 
ance of the plots after cutting. 
Live Stock, Poultry, and Feeding Stuffs. 
The Feeding Value of Different Varieties of Mangolds (Jour. Agric. 
Science, Vol. Hi., Pt. 3, September, 1910). — An investigation into the 
chemical composition of mangolds, which was begun in 1903 at Cam- 
bridge University, showed that the Long Red mangold, owing to its 
high yield and percentage of dry matter, produces about 20 per cent, 
more dry food per acre than any other variety. At the same time a 
series of feeding experiments was started in order to discover whether 
this superiority of the Long Red over the Globes and Tankards would 
be borne out in practical farming, that is to say, whether the feeding 
value of any type of mangold is proportional to its percentage of dry 
matter. The chemical investigation and the earlier feeding trials were 
noticed in the Journal for October, 1908, p. 538, but this paper contains 
a complete summary by Prof. T. B. Wood of the whole investigation 
which has been carried out by him since 1907. 
The points tested were the comparative feeding value of Yellow 
Globe and Long Red mangolds as constituents of a liberal fattening 
diet, the comparative feeding value of Golden Tankard and Long Red 
mangolds, also in a fattening diet, and the comparative feeding value 
of Yellow Globe and Long Red mangolds for store cattle. Every pre- 
caution was taken to choose for the experiment animals of uniform 
weight and capacity for growth, but, in spite of this, it was found 
that in a single trial the variation among the individual animals receiv- 
ing the same treatment was far greater than the quantity the experi- 
ment sought to measure, and Prof. Wood remarks that little reliance 
can be placed on the results of single experiments with the small 
number of animals commonly employed in feeding tests. The results 
of all the trials are discussed according to the methods used in the 
theory of probabilities in order to find which of the results obtained 
were really significant of some difference in the feeding value of the 
mangolds, and not due to variations in the capacity of the animals for 
Improvement, and the following conclusions are arrived at : — 
L 
Weight Cost 
of seed of seed 
per acre. per acre, 
lb. s. a. 
15 10 7 
221 14 7 
3Si 20 4 
17 120 
