161 



some the fore foot is wanting. The tracks, he thinks, are 

 batrachian, but whether all were made by batrachians of 

 the same species is doubtful. 



Dr. Charles T. Jackson presented a copy of the Report 

 of the Cochituate Water Board, and said, that as he was 

 not present at a former meeting of the Society, when Dr. 

 A. A. Hayes made a communication upon the Impurity of 

 the Cochituate Water, he would avail himself of the present 

 opportunity to make a few remarks upon the subject ; which 

 he proceeded to do as follows : — 



In presenting to the Society a copy of the Report of the 

 Cochituate Water Board, containing the Reports of Prof. Horsford 

 and myself, on the composition of the water of the lake and of 

 that delivered by the aqueducts in Boston, I would take the 

 opportunity of recording my dissent from the views presented to 

 this Society on this subject by my friends Dr. A. A. Hayes and 

 Dr. John Bacon. 



From careful analyses, and researches made by myself, I am 

 convinced that the taste and odor of Cochituate water are not 

 due to the presence of oil of fishes, either in a separate state or 

 in the bodies of Cyclopean crustaceans^ but are due to decompos- 

 ing vegetable matters, such as the mucilage and albuminous 

 matters of plants, as indicated by the presence of the associated 

 chlorophyl and myrica wax and oil contained in it. 



1st. The specific gravity of oil of fishes is such, that it would 

 float on the surface of water, and be seen as a film on its sur- 

 face ; while, in fact, we find the matter containing the oil in the 

 deep waters of the lake, and not on the surface. 



2d. The oil which is extracted from the myrica wax found in 

 the water, is soluble in alcohol, whereas fish oil is not soluble in 

 it. So far as the properties of oil extracted from Cochituate water 

 are known, it is identical with the oil which alcohol dissolves 

 from myrica or bayberry wax, which is generally found as a 

 glazing on green leaves and twigs of most plants. 



3d. That the taste and odor are not due to the presence of 

 Cyclops, would appear from the fact, that while the crustaceans 



PROCEEDINGS B. S. N. H. VOL. V. 11 APRIL, 1855. 



