MOSQUITOES AND PROSECUTIONS 303 
it possible that the trouble was caused by the pollution of the dam water by the 
sewage of a State institution nearby, and complained to the health officer. It 
seemed that the health officer was the attending physician at the State institu- 
tion, and, resenting the implication concerning the sewage of the institution and 
being familiar with the fact that mosquitoes carried malaria, he claimed that 
the trouble was due to the breeding of Anopheles mosquitoes in the mill dams 
or in the back waters caused by the dams. He therefore secured an order from 
the State Board of Health, demanding the abolition of the dams in the interest 
of health. This order was resisted by the proprietors of the mills and the case 
was brought before the courts. The proprietors speedily informed themselves 
on the subject of the etiology of malaria, reading all the latest publications on 
the subject. They then cleaned up the margins of the dam, presented a copy of a 
recently published book on mosquitoes to each of twelve physicians of the town, 
and offered a reward of $50 each for every Anopheles larva that could be found 
in the dams. The physicians all made search and no larve were found. Where- 
upon, each physician was summoned as an expert witness in the trial. In the 
meantime an expert entomologist was engaged to come to the town to examine 
the conditions at the dams and to find the breeding-places of Anopheles in the 
surrounding country. This expert found no Anopheles in the dams, but he 
found the mosquitoes breeding practically everywhere throughout the com- 
munity, with the exception of the dams. He found unused springs, chance pools 
and puddles swarming with Anopheles larve. He often found them (since it 
was at wet season) breeding in water standing in the furrows in the corn fields, 
the soil being a strong clay. 
At the first trial, expert testimony was brought forward to the effect that 
the mosquitoes probably bred in the marshes at some distance back of the dams, 
and that these marshes could not be drained so long as the dams remained. The 
case was adjourned and before the time of the next court the proprietors of the 
dams had bought certain portions of this back land and had successfully drained 
it, showing that the existence of the marshes was not necessarily due to the ex- 
istence of the dams. Ultimately, the case was nolle prosequt, and the dams re- 
main today. 
Another interesting case occurred in a town near Boston. A member of the 
Board of Health, greatly interested in the subject of malaria and malaria mos- 
quitoes, found Anopheles breeding extensively in certain stone quarries, particu- 
larly in the abandoned portions of the quarries which had been worked. The 
proprietors of the quarries were sued, with the idea of forcing them to fill up the 
abandoned portions of the quarries, and the case came to trial in Boston before 
atreferee. Expert testimony was heard and the judge finally announced, before 
hearing all of the testimony which was prepared, that he had no doubt from 
what he had already heard that the quarries were breeding malaria mosquitoes 
and that their existence constituted a menace to the health of the people living 
nearby ; but, that he would not decide in favor of the prosecution for the reason 
that such a decision would constitute a dangerous precedent, and that it would 
render all owners of excavations or mill dams or similar necessities to industry 
