12 REMEDIES AND PREVENTIVES AGAINST MOSQUITOES. 
In many small country towns, even where there is a water supply, 
tanks are to be found under the roofs to supply bathrooms. Such 
tanks should be screened, since mosquitoes gain entrance to the tank 
room, either through dormer windows or by flying up through the 
house from below, in search of places to lay their eggs. 
About a large old house or a public building there are so many 
of these chance breeding places that only the most careful and long- 
continued search will find them all. As an example, in a State 
hospital, after a search which lasted for many days, and after a 
treatment of all possible breeding places found, mosquitoes still con- 
tinued to annoy the patients. Finally in the darkest part of a 
disused cellar was found a half-barrel with standing water in it, 
which was giving out mosquitoes at the rate of hundreds per day. 
Frequent change of water or the use of kerosene will render all such 
breeding places harmless. 
In community work in cities all of the points mentioned must be 
borne in mind, and in the portions of the community where the resi- 
dences are for the most part villas, in the absence of swampy suburbs 
the householders are in the main responsible for their own mosquitoes. 
There are, however, breeding places for which the municipality may 
be said to be responsible, and these entirely aside from public foun- 
tains, reservoirs, or marshes. Roadside open gutters or ditches may 
breed a generation of any one of several species of mosquitoes, includ- 
ing malarial mosquitoes. On a pasture or common, where sod has 
been removed, water accumulating in the excavation thus formed 
may breed a generation of malarial mosquitoes. All such accidental 
breeding places should be abolished by filling in. 
It seems unlikely that in any general sewage system mosquitoes 
may breed in the sewers proper. That they do breed in the catch 
basins is well known. The purpose of the catch basin is to catch and 
retain by sedimentation sand and refuse which would otherwise enter 
the sewer and deposit in it. It is intended to be water tight and to 
hold a considerable body of water, which stands in it up to the level 
of the outlet pipe. Such catch basins are very commonly used in back 
yards and at the crossings of streets. The water is removed only by 
rain or when the street or yard surfaces are washed. In dry seasons 
the period of stagnation may last several weeks, certainly long enough 
for mosquito breeding. As a matter of fact mosquitoes in mid- 
summer do breed in such traps or catch basins by millions. These 
basins may be treated with petroleum, or the municipal authorities 
may flush them once a week, carrying away such larve as may have 
hatched. Kerosene treatment, however, is best. 
Public dumps are great breeding places, because here accumulate 
old bottles, cans, boxes, bits of tin or iron vessels, and other objects 
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