96 



on the other, in sleek and unbroken health. Some hundj-ed 

 acres are known to be thus stricken ; and for more than a 

 century the Knowltons and their ancestors, proprietors here, 

 have suffered and wondered at this infliction of nature. No 

 observation or experiment has yet revealed the cause ; the 

 mystery remains a mystery still. 



On a motion to that effect, Messrs. C. M. Tracy of Lynn, 

 A. W. Dodge of Hamilton, James Bartlctt of Wenham, and 

 Henry F. King of Salem, were made a commit.ee to investi- 

 gate this curious subject and report the results to the 

 Institute. 



James J. H. Gregory, of Marblehead, described the 

 geological features of our coart region, and particularly 

 dwelt upon the remarkable dykes of greenstone which almost 

 everywhere appear, cutting the granite or sienite at all sorts 

 of angles. In this vicinity the prevalent rock is nearly a 

 true granite, and is a very useful building stone. West- 

 ward, the greenstone type predominates, and the rock, 

 though worse for walls, is much better for macadamizing. 

 This hill, where we stand, is no doubt a vast pile of bowlders 

 and loose fragments, coated with a soil, comparatively thin, 

 formed from the decomposition of the rocks in part, with an 

 addition of accumulated vegetable matter. But few nota- 

 ble minerals are found here ; even the iron does not, proba- 

 bly, form over two per cent, ol the mass of the rock, but this 

 is quite enough to affect the compass-needle perceptibly. 



Rev. C. 0. Beaman of Salem, had visited " Rafes Cleft" 

 and the other remarkable spots in the vicinity, and had been 

 charmed with the beauty of the scenery he had fallen among. 

 He could congratulate the Institute on their good fortune 

 in meeting here ; and he could also congratulate the people 

 of Gloucester that the natural and historical features of the 

 place had received such fitting and satisfactory notice in the 

 recent history of the place by Mr. Babson. 



