Proceedings of Seventh Annual Meeting 49 



states that the commission itself is required to prevent mosquito 

 breeding through its own efforts and at its own cost. 



The second class of ''water conditions" is that wherein water is 

 artificially controlled for pleasure or commercial purposes, such as 

 lakes, reservoirs, ice and fish-ponds and mill-ponds. Under the 

 rule in this class, the owner is obliged to maintain his property free 

 of mosquito breeding at his own cost under the supervision of this 

 commission. 



In class 3 it frequently occurs that a natural and an artificial condi- 

 tion exist at the same time. Thus, the building of a railway embank- 

 ment through the middle of a natural swamp, or the creation of a 

 spring bog by the raising or lowering of water, are instances of which 

 many more could be cited. The rule under this third class fixes a 

 joint responsibility and the adjustment of the costs is made the sub- 

 ject of agreement between the commission and the property owner. 



In considering the first proposition, it seems eminently proper that 

 the full cost should fall upon the commission because in the doing 

 away of a general mosquito nuisance created by nature, the greatest 

 benefit is derived by the public at large, with but a small degree, if 

 any, by the land owner. 



Under the second class, that of the artificial impounding of water, 

 a careful consideration of the matter leads to the conclusion that the 

 property owner should be charged with the cost of maintaining his 

 artificial water area so that no nuisance is allowed to occur, because 

 in changing nature's plan to that of his own, he has created a mos- 

 quito-breeding condition many times larger, from which he derives 

 pleasure or profit at the public's increased disadvantage. It would, 

 therefore, seem equitable that having caused this condition, he should 

 be held accountable for its maintenance. 



The purpose of creating the third or joint responsibility class is 

 self-evident. It is of constant occurrence that a natural condition 

 under the control of this commission is partly altered, or what was 

 artificial, reverts, through neglect or direct intention, to a natural 

 condition. The object, therefore, of this rule is to meet these con- 

 stantly changing conditions and properly and fairly to fix and de- 

 termine through mutual understanding, the costs and responsibility 

 to be borne and assumed by both the commission and the property 

 owner. 



It has been the policy of this commission to live up to and en- 

 force the rules governing these classes. Therefore, under class i, 



