240 A VISIT TO ItOTIIAMSTED. 



manure beiiif^", as a rule, applied year after year on the same 

 plot." Experiments on an actual course of rotation, with different 

 manures, have also been made. 



The following table shows the cropping, the breadth under 

 each experiment, and the duration of each : — 



Samples from all these plots are taken annually, and are 

 weigiied, dried, and preserved in the laboratory. Duplicate 

 samples are dried at 100° C. to determme their dry matter, and 

 then they are burnt on platinmn dishes in muffle furnaces, and 

 their ash preserved for future analysis. 



In many cases the amount of nitrogen is immediately deter- 

 mined, in others the sugar is estuuated, and other estimations 

 made, according to the kind of crop and the aim of the experi- 

 ment. The various soils are also being frequently analysed; 

 and, in the able hands of Mr E. Warrington, an extensive 

 investigation regarding the nitrogen in various soils is being 

 systematically carried out. 



The rainfall has been accurately measured during twenty-five 

 years in an ordinary rain guage, and also in a larger guage 

 -j-Q^Q^th of an acre in area. 



Besides these regular observations and investigations, special 

 subjects have been made matters of research from time to time, 

 — such as the transpiration of water by plants, tlie botanical 

 relations of plants under various systems of treatment, tlie 

 assimilation of nitrogen by plants, &c. 



The experiments with animals, once conducted on a great 

 scale at Rothamsted, have been discontinued or nearly so. The 

 oljjects of these important experiments were to deterndne tlie 

 relation between the character and amount of food consumed 



