282 
NATURE 
[OcTOBER 30, 1913 — 
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 dis- 
coveries which, apart from their great academic in- 
terest, may at once be turned to account by the cul- 
tivator. The constant renewal of expensively pre- 
pared 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 Valley growers. 
For my second instance of scientific work which 
has given results of direct value to farmers, J must 
ask to be allowed to give a short outline of the wheat- 
breeding investigations of my colleague Prof. Biffen. 
Even as late as fifteen years ago plant-breeding was 
in the purely empirical haphazard stage. Then came 
the rediscovery of Mendel’s iaws 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 valuable 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-ripen- 
ing 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 Bedfordshire and Dorset, but has not done 
well in Norfolk. The other variety, Little Joss, suc- 
ceeds much more generally. In a series of twenty- 
nine trials scattered 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 Ghirka. Its grain is the quality of 
ordinary English wheat. It tillers exceptionally well 
in spring, and is practically rust-proof. Its one draw- 
back is 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. 
The importance of this work is not to be measured 
only by the readiness with which the seed of the new 
varieties has been tried by farmers and the extent to 
NO. 2296, VOL. 92] 
‘inconclusive. : 
which it has succeeded. The demonstration of the — 
inheritance of immunity to the disease known as 
yellow rust, the first really aecurate contribution to 
the inheritance of resistance to any kind of disease, — 
inspires hope that a new method has appeared for the © 
prevention of diseases in general. : 
Biffen’s work too shows the enormous value of co-— 
operation between the investigator and the buyer in 
defining problems connected with the improvement of — 
agricultural produce. It is open to doubt if a com- 
mittee of farmers would have been able to define the 
problems of English wheat production as was done 
by the Millers’ Committee, and in the solution of any — 
problem its exact definition is half the battle. Mac- 
kkenzie and Marshall in their work on the ‘* Pigmenta- 
tion of Bacon Fat’’ and on the spaying of sows for 
fattening, have found the great value of consultation 
with the staffs of several large bacon factories. There 
seems to be in this a general lesson that before taking 
up any problem one should get into touch not only 
with the producers but with the buyers, from whom 
much useful information can be obtained. 
I feel that Biffen’s work has borne fruit in still 
another direction, for which perhaps he is not alone 
responsible. Twenty years ago agricultural botany 
took a very subsidiary position in such agricultural 
examinations as then existed. In some of the agricul- 
tural teaching institutions there was no botanist, in 
others the botanist was only a junior assistant. It is 
largely due to the work of Biffen and the botanists at 
other agricultural centres that botany is now regarded 
as perhaps the most important science allied to agri- 
culture. : 
I must here repeat that I am not attempting to 
make a complete survey of all the results obtained in 
the last twenty years. My object is only to pick out 
some of the typical successes and failures and to 
endeavour to draw from their consideration useful 
lessons for the future. So far I have not referred 
to the work which has been done in the nutrition of 
animals, and I now propose to conclude with a short 
discussion of that subject. The work on that subject 
which has been carried out in Great Britain during 
the last twenty years has been almost entirely confined 
to practical feeding trials of various foods or mixtures 
of foods, trials which have been for the most part 
It has been shown recently that if a number of 
animals in store condition are put on a fattening diet, 
at the end of a feeding period of twelve to twenty 
weeks about half of them will show live-weight in- 
creases differing by about 14 per cent. from the 
average live-weight increase of the whole lot. In 
other words, the probable error of the live-weight 
increase of a single fattening ox or sheep is 14 per — 
cent. of the live-weight increase. This being so, it is 
obvious that very large numbers of animals must be 
employed in any feeding experiment which is de- 
signed to compare the feeding value of two rations 
with reasonable accuracy. For instance, to measure 
a difference of 1o per cent. it is necessary to reduce 
the probable error to 3 per cent. in order that the 
1o per cent. difference may have a certainty of thirty 
to one. To achieve this, twenty-five animals must be 
fed on each ration. Those conversant with the 
numerous reports of feeding trials which have been 
published in the last twenty years will agree that in 
very few cases have such numbers been used. We 
must admit then that many of the feeding trials 
which have been carried out can lay no claim to 
accuracy. Nevertheless, they have served a very 
useful purpose. From time to time new articles of 
food come on the market, and are viewed with sus- 
picion by the farmers. These have been included in 
