OP ARTS AND SCIENCES. 81 



portance in this country, and the most minute inquiries in this direction 

 are full of interest. 



After the exclusion of high tides from Mystic Pond, analyses prove 

 the continued presence of an undue amount of sea-water constituents 

 in the greatest depths. F'rom obvious sources, dissolved organic com- 

 pounds are daily added to the water ; and, if the purity of this important 

 supply of water is to be preserved, both restrictive measures and care- 

 ful engineering devices will be required. 



The details of observations made on this water would extend this 

 I^aper to great length. Belonging to the chemical history of waters, 

 they have more of an economical than strictly scientific importance ; 

 and this remark applies to the observations made in other bodies of 

 water. 



VOL. I. 11 



