119 



over the opening. It has thus been turned to account in sup- 

 plying steam engines and factories near the wharves ; and at 

 Swampscot beach affords an excellent supply for domestic 

 purposes, by piercing the sand and clay. 



The rate of subsidence is so gradual and slow that no indica-^ 

 tions of the cause is seen by any agent apparent to common 

 observation. Whether the whole Eastern coast of Massachu- 

 setts is not slowly settling is a matter for the consideration of 

 the geologist. We may hazard the conjecture, that the cause 

 of the settling of this extensive marsh may be found in the 

 current of water in the diluvium under the clay. The supply 

 comes from the rocky ledges of the hills, and in its passage under 

 the clay towards the sea, its only apparent outlet, it may take 

 along in its volume small particles of the debris of the aluvium, 

 and carry them to the ocean. This amount though small and 

 slowly carried would ultimately accomplish the result. The 

 numerous borings through the clay show that the current is 

 quite strong. In many cases the volume of water which fol- 

 lowed the auger, brought with it not only fine particles of sand, 

 but pebbles half an inch in diameter. 



The facts and phenomena which we have described as pecu- 

 liar to the Lynn Marshes, we find to be characteristic of the 

 extensive salt marshes of Ipswich, Rowley and Newbury. — , 

 Even the bed of clay and fresh water springs are found under 

 like circumstances, showing the entire similarity of the forma- 

 tions. 



On motion of George Andrews, a vote of thanks was passed 

 unanimously, for the interesting communication of the author. 

 Voted, to adjourn. 



Friday, February 27, 185T. 



Evening meeting at half -past seven o'clock, the President, 

 Daniel A. White, in the chair. 



Records of preceding meeting read. 



Donations to the Library were announced from Wm. Brown, 

 Wm. Mack, Alfred Stone, Charles Mason U. S. Commissioner 

 of Patents, Wm. H. Prince, T. Ropes, Charles H. Galloup of 

 Wenham, D. A. White. 



Donations to the cabinets, from George A. Perkins, H. J. 

 Pratt, Mrs. Kimball. 



