50 
FURTHER CONTRIBUTIONS ON CARBON BISULPHIDE 
TREATMENT OF SOILS. 
B. Heinze. Centr. Bakt. Parasitenk., Zweite Abth., 18 [1|3], 56- 
74; [7|9], 246-64; [13|15], 462-70; [24|25], 790-8 (1907).— Soil treated 
with CS 2 gave a better yield of potatoes, rye, oats, sugar-beets and 
grapes than did untreated soil. The CS 2 works directly on the micro- 
organisms of the soil retarding the growth of some, stimulating the 
growth of others, and besides, it acts indirectly on the mineral con- 
stituents of the soil. CS 2 increases the available nutriment by giving 
a more active growth of micro-organisms, moulds, bacteria, etc., 
which produce CO« and organic acids, and by forming some H 2 SO t 
through the oxidation of S. These acids then dissolve some of the 
mineral salts in the soil. Ca, K, and Mg were found to be increased, 
but the author could not prove that the available phosphates were 
increased. CS 2 works differently on the different organisms, such as 
algae, moulds, yeasts and bactenia. The micro-organism which 
brings about fermentation was restrained and the N assimilating 
micro-organisms especially azotobacter, were favored by the conse- 
quent preservation of a rich supply of carbon in the form of pectin, 
soluble humus material, pentpsan, etc. In brief, CS 2 produces a sat- 
isfactory soil condition for the N collecting micro-organisms espe- 
cially azotobacter. CS 2 inhibits the growth of plant parasites of an 
animal nature. How it affects parasites of a plant nature, is yet to 
be determined. By the CS 2 treatment, however, soil can be easily 
freed from weeds. CS 2 treated soil retains its moisture better than 
untreated soil and in sandy soils, nitrification is lessened, and the 
loss of nitrate by leaching is reduced. By the addition of a small 
amount of CS 2 to the soil shortly before cultivation, it is possible to 
determine which plants secure their N, mainly from nitrate, and 
which from ammonia, since the CS 2 inhibits nitrification for a time, 
so that the plants must obtain their N from ammonia directly. CS 2 
is of great value in overcoming soil sickness (Bodenmiidigkeitserchei- 
nungen) in case of vines, peas and clover. Oberlin has shown that 
the soil sickness of vineyards, which in many regions occurs per- 
iodically, can be counteracted by treating the soil with CS 2 . Clover 
sickness was remedied by treating the soil with CS 2 and the nodules 
developed despite the treatment. The author would explain the im- 
provement in these cases by the inhibition of the micro-organisms 
w'hich produce the toxic condition, since, in distinction from soil 
exhaustion, soil sickness is not remedied by fertilizers. Sterilization 
improved vine development in these soils but not in normal soil. 
Before replanting vineyards it is necessary to allow the soil to rest 
for some time. This resting time is shortened by the use of CS 2 and 
further, such treatment gives a better growth to the vine and a better 
ripening of the grapes. Thiocarbonates, sulphates, mustard oils and 
even green mustard will work on the soil as CS 2 does. 
M. X. Sullivan. 
