210 The Rothamsted Grass Experiments. 



the number of days in each month when the rainfall exceeded 

 O'Olin., together with the monthly mean iriaximum tempera- 

 ture, the monthly mean minimum temperature, the monthly 

 mean temperature, and the monthly mean range of tempera- 

 ture, all at Greenwich. Further, in the respective tables, 

 there are given, for each season, the total rainfall, the total 

 number of days on which O'Olin. or more fell, and the means 

 for each item of temperature : 



1. For the total 12 months ; July to June inclusive ; 



2. For 4 months July to October ; 



3. For 4 months November to February ; 



4. For 4 months March to June : 



5. For 3 months April to June ; 



6. For 2 months April and May. 



With each of the five very different conditions of manuring 

 (on plots 3, 7, 9, 11, 14) the year 1869 gave the highest amount 

 of produce. On the other hand, 1870 gave, with two out of 

 the five conditions of manuring, the lowest produce, with two 

 others the lowest but one ; but the remaining or nitrated 

 plot was an exception, giving, in this year of drought, 1870, 

 an abnormally high produce for the season a fact which was 

 considered when the general results on plot 14 were under 

 discussion. There can be no hesitation, therefore, in taking 

 the season of 1869 as that of the highest productiveness of 

 the twenty, and that of 1870 (with the exception mentioned) 

 as one of the lowest productiveness ; the next in order in this 

 latter respect being 1874. The produce of these two most 

 contrasted seasons is set forth in Table LIV., page 211, where 

 also a comparison is made with the average of the twenty 

 years, and the deficiency in 1870 compared with 1869. 



A very full table, not given here, shows some of the 

 meteorological conditions under which the two very different 

 crops were grown. 



The lowest line in Table LIV. shows that (excluding the 

 nitrate plot 14) there was an average yield per acre of nearly 

 40001b. (about If tons) more hay in 1869 than in 1870; 



