I 1 THE BO i. 1 XICAL MAGAZINE. [V oi. xxi. No. 245. 



added. After tour davs, the alga? were dead in the flask with 

 1 naphthalene, while they remained alive for several weeks in 

 the flask with 0.1 ^ naphthalene. This led me to the suspicion 

 that the perfectly white naphthalene contained some impurity, 

 and therefore it was treated with sodium carbonate to extract 

 organic acids, but such were not found. Another portion was 

 warmed with hydrochloric acid and this extract evaporated to 

 dryness. A small amount of crystallized substance was thus 

 obtained, which upon addition of caustic potash yielded small 

 droplets of a strong and decisive odor of quinoline. 



My tests with bacteria showed that 0.1^ naphthalene does 

 not prevent entirety bacterial growth but may supress the 

 development to a varying degree when added to bouillon in- 

 fected with Bacillus prodigiosus, B. fluorescens. liquilaciens, B. 

 mycoides, B. pyocyaneus and B. subtilis respectively. B. tny- 

 coides is less injured than B. prodigious and B. subtilis. 



Experiment with Barley and Pea. 



Pots filled with 10 K of unmanured loamy soil received as 

 general manure, g : 



For barley. For pea. 



Ammonium nitrate 5 0.1 



Sodium phosphate 5 5 



Potassium sulphate 3 3 



For each plant, one pot served as check pot, two other pots 

 received each 1 gram of naphthalene well mixed with the soil, 

 while one pot received 5 grams naphthalene. After several 

 months decisive differences were noticed which, however, did not 

 perfectly correspond in both series ; 1 gram naphthalene caused 



') Since recently the remarkable fact was reported by Kahn (Centr.-Bl. Bakt. 

 II. 7'i. .'>82j that a hydrocarbon like paraffine can be attacked by a mould fungus and 

 serve ;<• tl"- BOUrce of carbon, and further a communication was made by SoHNGEN 

 (Centr.-Bl. Bakt. II. L5, 513) that also methane can serve as a source of carbon for a 

 kind of bacterium (Bacillus melhanicue), J have been led to test whether well purified 

 naphthalene would serve as a source of cabon for certain bacteria, such as B. fiuores- 

 cens liquifaeiena and /;. metltylicue. The result was entirely negative as I had expected. 



