96 Journal of the Mitchell Society \Scpteni'ber 



a])ly an amido eompouiid derived from decomposition of tankage or 

 some form of animal nitrogen, we determined the nitrgen in samples 

 of the fertilizer after it had been rendered harmless. The percentage 

 was higher than in the original sample. This, however, may be due 

 fact that the water content had been changed. Unfortunately, we had 

 not determined this in the original samples. AVe carried through a 

 set of experiments to see how many organic substances containing 

 nitrogen were toxic to tobacco plants. 



These experiments showed several substances that were quite toxic, 

 notably the nitro phenols, pyridine and piperidiue. This was but a 

 confirmation of experiments conducted by Cameron. Here is an in- 

 teresting problem that deserves the attention of the fertilizer manu- 

 facturer, especially in this day, when he is ransacking the world to 

 find sources of potash and nitrogen. In the future will it not leave the 

 manufacturer liable if he sells a fertilizer with a guarantee that it will 

 grow a particular crop and it is found to injure it? 



In this particular case the tobacco fertilizer did enormous damage. 



It can be rendered harmless in a very simple way, but it is the 

 manufacturer's job to discover this and not the farmer's. This should 

 lead to the testing out of samples of every fertilizer sold for a par- 

 ticular crop. 



Davidson, N. C. 



