74 



GENERAL AGRICULTURAL NOTES. [Sept. 1894. 



of 600 square yards to be planted with potatoes, were treated 

 with sulphide. By the side of these sulphurated plots equal 

 areas which had not been so treated were reserved to constitute 

 control plots. 



Unfortunately, all the wheat at Gonesse was laid, and it was 

 found impossible to weigh it ; but at J oinville the potato crop 

 upon the 600 square yards sulphurated showed an increase of 

 weight varying from 5 '3 to 38-7 per cent. A more methodical 

 series of experiments was carried out in 1891 and 1892. At 

 J oinville, a piece of poor gravelly soil was selected. Two strips 

 of 600 square yards each were measured off side by side. One 

 was surrounded by a ditch a yard wide and a yard deep ; the 

 other remained in communication with the surrounding soil. 

 Neither of these strips received any manure. The one 

 surrounded by ditches was dosed with 72-6 lbs. carbon bi- 

 sulphide per 120 square yards. Each strip was then divided 

 into five squares of 120 square yards each, in order that com- 

 parison might be made of five separate crops, viz., wheat, oats, 

 beet, potatoes, and clover. The result showed an increased 

 yield upon the sulphurated area similar to that which occurred 

 in 1888 and 1889. This increase was especially remarkable in 

 the case of clover. 



Finally, in 1892, in order to determine whether the influence 

 of carbon bi-sulphide may be prolonged beyond one year, the 

 same crops were sown upon the same areas, the relative 

 positions, however, being changed. There was no applica- 

 tion of manure, nor of sulphide. Once more an increase of 

 crop occurred, but much more marked than in the preceding 

 years, owing, it is considered, to the influence of the drought 

 upon the normal cultures in a soil so poor as that of the farm 

 in question. The results of the entire series of experiments 

 carried out in the years 1888, 1889, 1891, and 1892 may be 

 briefly summarised as follows: — Comparing the sulphurated 

 sections with the control plots, it appears that on the former 

 areas there was an increased yield of wheat ranging from 15 to 

 46 per cent, in the grain and from 21 to 80 per cent, in the 

 straw. Potatoes on the sulphurated section gave an increased 

 yield of from 5 to 38 per cent., and the production of beetroot was 

 from I S to 29 per cent, superior to the yield obtained on the 

 control plots. Clover gave an increased yield on the treated 

 areas ranging from 67 to 119 per cent. ; and in the case of oats 

 the treatment produced, in 1891, an increase of 9 percent, in the 

 grain and 30 per cent, in the straw ; while at Joinville, in 1892, 

 the oats on the sulphurated plots are stated to have shown an 

 increase of 100 per cent, in grain, and 60 per cent, in straw. 



These results are considered to show most unmistakably the 

 effect produced upon the yield of a crop by the injection of 

 carbon bi-sulphide into the soil. It must be remembered, 

 however, that the experiments were conducted on comparatively 

 small areas. 



