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suggested that the factor causing sterility in these cases was biological in nature, 
that it consisted, in fact, of some kind of organism inimical to the useful fer- 
mentation bacteria, and more easily killed than they by heat or antiseptics. 
After a long series of admirable scientific investigations these workers and their 
colleagues have shown that soils contain many species of protozoa, which prey 
upon the soil bacteria, whose numbers they keep within definite limits. Under 
certain circumstances, such, for instance, as those existing in the soil of sewage 
farms, and in the artificial soils used for the cultivation of cucumbers, tomatoes, 
&c., under glass, the protozoa increase so that the bacteria are reduced below 
the numbers requisite to decompose the organic matter in the soil into substances 
suitable for absorption by the roots of the crop. Practical trials of heating such 
soils, or subjecting them to the action of toluene, or other volatile antiseptics, 
have shown that their lost efficiency can thus be easily restored, and the method 
is now rapidly spreading among the market gardeners of the Lea Valley. 
I have attempted to sketch the chief points of this subject with some detail 
in order to show that strictly scientific work, quite outside the scope of what some 
people still regard as ‘practical,’ may result in discoveries which, apart from 
their great academic interest, may at once be turned to account by the cultivator. 
The constant renewal of expensively prepared soil which becomes ‘sick’ in the 
course of a year or so is a serious item in the cost of growing cucumbers and 
tomatoes. It can now be restored to fertility by partial sterilisation at a fraction 
of the cost of renewal, and considerable sums are thus saved by the Lea Valloy 
growers. 
For my second instance of scientific work which has given results of direct 
value to farmers, I must ask to be allowed to give a short outline of the wheat- 
breeding investigations of my colleague Professor Biffen. Even as late as 
fifteen years ago plant-breeding was in the purely empirical haphazard stage. 
Then came the rediscovery of Mendel’s Laws of Heredity, which put in the 
hands of breeders an entirely new weapon. About the same time the Millers’ 
Association created the Home-grown Wheat Committee, of which Biffen was a 
member. Through this Committee he was able to define his problem as far as 
the improvement of English wheat was concerned. There appeared to be two 
desiderata: (1) The production of a wheat which would crop as well as the 
best standard home-grown varieties, at the same time yielding strong grain, 
i.e., grain of good milling and baking quality; and (2) the production of varieties 
of wheat resistant to yellow rust, a disease which has been computed to decrease 
the wheat crop of the world by about one-third. 
The problem having been defined, samples of wheat were collected from every 
part of the world and sown on small plots. From the first year’s crop single ears 
were picked out and grown on again. Thus several hundred pure strains were 
obtained. Many were obviously worthless. A few possessed one or more valu- 
able characteristics : strong grain, freedom from rust, sturdy straw, and so on. 
These were used as parents for crossing, and from the progeny two new varieties 
have been grown on, thoroughly tested, and finally put on the market. Both 
have succeeded, but both have their limitations. Burgoyne’s Fife, which came 
from a cross between strains isolated respectively from Canadian Red Fife and 
Rough Chaff, was distributed by the Millers’ Association after a series of about 
forty tests, in which it gave an average crop of forty bushels per acre of grain, 
which milled and baked practically as well as the best imported Canadian wheat 
It is an early-ripening variety which may even be sown as a spring wheat. It 
has repeatedly been awarded prizes for the best sample of wheat at shows, but 
it only succeeds in certain districts. It is widely and successfully grown in Bed 
fordshire and Dorset, but has not done well in Norfolk. The other variety, 
Little Joss, succeeds much more generally. In a series of twenty-nine trials scat- 
tered between Norfolk and Shropshire, Kent and Scotland, it gave an average of 
forty-four bushels per acre, as compared with forty bushels given by adjoining 
plots of Square Head’s Master. It originated from a cross between Square 
Head’s Master and a strain isolated from a Russian graded wheat known as 
Glinka. Its grain is the quality of ordinary English wheat. It tillers excep- 
tionally well in the spring, and is practically rust-proof. Its one drawback ‘s 
its slow growth during the winter if sown at all late. It has met with its 
greatest success in the Fen districts, where rust is more than usually virulent. 
