466 SOILS: PROPERTIES AND MANAGEMENT 



was before such treatment. The beneficial effect of the 

 treatment extended to the second year. 



Oberlin found a somewhat similar condition where 

 the soil of vineyards treated with carbon bisulfide to kill 

 phylloxera showed greatly increased productiveness after 

 the treatment. The effect of carbon bisulfide on the 

 vineyard soil was to make it possible to raise grapes con- 

 tinually on the same land, whereas it had previously been 

 necessary to rest the land by growing a succession of 

 other crops at intervals of several years. It was noticed, 

 however, that immediately after treatment the plants did 

 not grow so well as under normal conditions. Systematic 

 investigations of the subject then began, and as early as 

 1895 Pagnoul 1 reported that when carbon bisulfide is 

 applied to soils nitrification is temporarily depressed. 



Investigation of the effect of heat on soil had begun 

 somewhat earlier, when Frank 2 showed in 1888 that it 

 increases the quantities of soluble matter, both organic 

 and inorganic, as well as causing the soil to be more pro- 

 ductive. 



The subject has been investigated by a large number of 

 persons, and in addition to carbon bisulfide a considerable 

 number of other volatile antiseptics, including ether, 

 chloroform, and toluene, have been found to influence the 

 productiveness of soils. The effect of heat, particularly 

 in steam, at various temperatures from slightly above 

 normal to more than 200 C., has also been studied, whiL 



1 Pagnoul, M. Nouvelles Recherches sur les Transforma- 

 tions que Subit 1'Azote dans le Sol. Annales Agronomique, 

 Tome 21, pp. 497-501. 1895. 



2 Frank, B. Ueber den Einfluss welchen das Sterilisiren 

 des Erdbodens auf die Pflanzen Entwickehmg ausiibt. Ber. 

 d. Deut. Bot. Gesell. (Generalversainmlungs Heft) Band 4, 

 Seite 87-97. 1888. 



