PROCEEDINGS OF THE CHEMICAL DEPARTMENT. 



399 



the two centre drills, although containing a larger number of 

 plants, while the north drill is not greatly increased. The dif- 

 ference here may be fairly attributed to the solubility of the 

 sulphate of aramouia, which causes it to mix easily with the 

 soil, and so affect the adjacent plants, while glue, being practi- 

 cally insoluble in cold water, lies where it is placed, and only 

 yielding its ammonia by decomposition, that substance is ab- 

 sorbed by the roots near which it is generated before ic has time 

 to permeate the soil and reach the adjoining plants. It is re- 

 markable that in the great majority of instances the sum of the 

 weights of the two outer drills materially exceeds that of the 

 two inner ones. This is better seen in Tables IV. and V., 

 which give the details of the experiments arranged in the same 

 manner as those of the other experimenters. 



Experiments made by Mr. John Richardson, Drylawhill, 



Prestonkirk. 



The soil in this case was a fine turnip soil, with an open 

 subsoil, situated about eighty feet above the level of the sea. 

 The previous cropping was Swedes, wheat, hay, tares, and then 

 the experimental turnip crop. The rainfall during- the summer 

 and autumn months, as observed at East Linton, about one 

 mile from the experimental field, by Mr. Storie, was : — 



The plots were sown on 13th June, arranged exactly as in 

 the plan contained in the Instructions (page 390), and under 

 favourable circumstances. The weather on the following day 

 was dry, but slight showers fell on the 15th, 16th, and 17th. 

 On the 20th, the braird began to show oir that part of the field 

 which was sown in the forenoon, and on the following day the 

 remainder could be detected. On the 24th, the dry weather 

 was seen to be operating disadvantageous^, and owing to the 

 attacks of the fly, Mr. Eichardson feared the crop might never 



