86 TREE WOUNDS AND DISEASES 



with the drainage of certain chemical works ; 

 and in another case an unhealthy condition of 

 the Scotch and Austrian pines was brought 

 about by sewage that had been allowed to pass 

 over the surface of the ground from neigh- 

 bouring dwellings. 



Near the main entrance to the Tower of 

 London and Billingsgate Fish Market, con- 

 siderable difficulty was experienced in getting 

 the plane trees established, though the question 

 of suitable soil and the choice of sturdy, well- 

 rooted specimens had received due attention. 

 At last it was found that the drip from the 

 fish carts was the cause of the evil, a remedy 

 for which was quickly found. But such cases 

 are by no means uncommon in towns, and, 

 in some of the gardens along the Thames 

 Embankment and at Westminster, trees and 

 shrubs have suffered from the effects of treat- 

 ing the roads with asphalt and similar com- 

 positions. 



Not a few of the sudden and mysterious 

 deaths of healthy town trees can be directly 

 attributed to an escape of gas. Of all trees, 

 those growing in our greater centres of industry 



