747 



Brizi considers the action of the gases contained in the acetylene and the 

 admixtures to be a displacement of the normal air, containing oxygen, so 

 that the roots suffocated and he thinks that illuminating gas will act similarly 

 but more powerfully. The moisture in the soil, therefore, favors the injury 

 because it reduces the imperviousness of the soil to the gas. This theory of 

 Brizi's of the suffocating effect on the roots exercised by illuminating gas, 

 together with the products its contains, finds support in so far that I have 

 perceived clearly the odor of butyric acid when cutting the roots of lindens 

 in Berlin after poisoning from gas and I could determine a violet brown 

 discoloration of the membrane of roots of trees which had died because of 

 stagnant water. 



