February, 1912.] 



141 



Scientific Agriculture. 



origin of fat in the animal's frame. But 

 the science of nutrition has now passed 

 out of that early region of first approx- 

 imations : we know that carbohydrates 

 and fats supply energy which can be 

 stored in known ratios ; we know, 

 roughly, what quantities of protein are 

 required to maiutain the tissue wastage. 

 What is now required is an attack upon 

 a much more refined class of problem — 

 why an animal' in the last stages of 

 fattening responds so well to linseed 

 cake and acquires a special kindly feel 

 and appearance on this food alone ; why 

 again cotton cake and barley meal 

 "nick "so well together; why again 

 oats must not be fed to horses until they 

 have been in store foi a certain length 

 of time. These are all questions which 

 depend upon much more delicate methods 

 of analysis than those hitherto available, 

 because they deal with constituents un- 

 touched in the first approximation to 

 the composition of the material present 

 perhaps only in minute proportions. 



The influence of climate and season 

 has naturally received much attention 

 at Rothamsted but it cannot be said 

 that any great advances have yet been 

 made in the way of correlating meteoro- 

 logical statistics with growth. Temper- 

 ature and water supply are without 

 doubt fundamental factors in determin- 

 ing yield ; the difficulty that attends 

 the problem seems to be the collection 

 of data that are really critical. For 

 instance, everybody will agree as to 

 what constitutes a spell of " growing 

 weather" in spring but it is difficult — 

 we may almost say it is impossible— to 

 define such growing weather in terms 

 of the constants usually determined at 

 a meteorological station or to pick out 

 from an inspection of the daily readings 

 when such a period has taken place in 

 the past. Without doubt the climate 

 chiefly affects a crop by the variations 

 it induces in the water content of the 

 soil, a factor which also depends upon 

 the physical texture of the soil and the 

 treatment to which it is subjected. A 

 certain amount of attention has been 

 given to these points at Rothamsted in 

 the past : for example, determinations 

 have been regularly made of the amount 

 of water percolating through the soil, 

 of the effect of the growth of plants 

 upon the water content at different 

 times of the year and again, of 

 the changes in the texture of the 

 soil— which determines both its reten- 

 tiveness and permeability— caused by 

 the long-continued applications of 

 particular manures. It is probable, how- 

 ever, that investigations of this kind will 



play in the future a more considerable 

 part, as the importance of the physical 

 behaviour of the soil begins to be recog- 

 nised by scientific men. We have to 

 remember that the labours of the farmer 

 in the spring are almost entirely directed 

 to getting the soil in a particular physical 

 condition; that which he calls " a good 

 seed bed" and the subsequent growth of 

 the crop will depend far more upon the 

 mechanical texture it has acquired than 

 upon the amount ot manure it may re- 

 ceive. When the farmer speaks of the 

 field as having been exhausted by the 

 growth of a crop of wheat he refers far 

 more to the bad mechanical condition it 

 has reached than to the comparatively 

 small withdrawal of plant-food and most 

 of the objections which from time to time 

 have been taken by farmers, with reason 

 on their side, to particular artificial 

 manures are really due to their secondary 

 effects upon the tilth of the soil. In the 

 importance which is now being given to 

 the physical aspect of the soil we see 

 again how far we have travelled from 

 the early conception of the soil as a mere 

 magazine of ready-formed food which 

 prevailed for some time after the Roth- 

 amsted experiments were started. It 

 would be possible to go on definitely 

 indicating what work remains to be done 

 and what problems are still unattacked 

 in such a well-worn subject as to the 

 relation of the plant to the soil ; sufficient 

 has been said to show how big the task 

 is before the farmer can acquire anything 

 like the control of the soil which the 

 manufacturer either of metals or of tex- 

 tiles, possesses over his materials. This 

 control is likely to be more necessary to 

 the English farmer than to any other ; 

 in no other country is the price of land 

 so high nor the pressure of the popula- 

 tion so great ; in no other country, there- 

 fore, is there such a necessity for inten- 

 sive farming and for utilising the soil up 

 to its utmost capacity. That the impor- 

 tant farming districts of England do at 

 the present time still show a higher pro- 

 ductivity than similar areas in any coun- 

 try is in no small degree due to the man- 

 ner in which the farmer has assimilated 

 the lessons of the Rothamsted experi- 

 ments during the period of expansion and 

 development in all districts which took 

 place from about 1840 to 1860 or 1870. 

 Now that a fresh wave of prosperity 

 seems to be coming to British agriculture 

 accompained by an increased intellectual 

 activity and curiosity among the culti- 

 vators of the land, we may hope that 

 the later researches at Rothamsted may 

 find both appreciation and translation 

 into practice at the hands of the work- 

 ing farmer. 



