234 W. S. BAYLEY — SYENITES FROM NEW ENGLAND. 



to say positively whether the rock exists merely in bowlders or whether 

 some of it may not be in place. A little north of east of South Litchfield 

 the sodalite-bearing eleolite-syenite is again met with, on the eastern 

 slope of a glacial ridge on the western side of the southern end of Coch- 

 newagon pond in the town of Monmouth. Mr. Clough, who has carefully 

 explored the region thereabout, asserts that the rock is found in a stretch 

 of country running about northwest and southeast, with a width of only 

 a few rods and a length of about two miles. Within these limits bowl- 

 ders may be picked from any of the stone walls surrounding the tiel<!>- 

 Beyond them the syenite has not yet been discovered. At Cochnewagon 

 pond the bowlders of eleolite-syenite occur in considerable numbers 

 with others of gneiss, granite and schist, principally at the base of a 

 gravel and sand ridge that rests upon a foundation of slate. There is no 

 question but that in this case the rock is not in place. It lias undoubt- 

 edly been transported thither from somewhere toward the northwest* 



From a consideration of the statements above made, it would seem 

 probable that all of the eleolite-syenite of the towns of West Gardiner, 

 Litchfield and Monmouth has come from a region beyond the limits of 

 these towns, and that nowhere within them does the rock occur in place. 



Macroscopic Description. — The macroscopic- appearance of the Maine 

 eleolite-syenite is too well known to need much description. Its most 

 noticeable features are the large masses of bright yellow cancrinite and 

 deep blue sodalite and the brilliant plates of black mica that spot 

 its otherwise almost snow-white surface. Here and there light brown 

 zircon f crystals are imbedded among the other constituents, but they 

 are by no means so numerous as museum specimens would seem to 

 indicate. Among the lighter minerals that can be distinguished in the 

 hand specimen, the most abundant is a white feldspar, often occurring 

 in large columnar crystals from a quarter to a half inch in length. They 

 have a distinct cleavage and a pearly luster on cleavage surfaces. Their 

 specific gravity varies between 2.608 and 2.600. A partial analysis of 

 pieces picked from a hand specimen is reported by Dr. Clarke J to have 

 yielded — 



This feldspar, which is undoubtedly albite, is the most prominent one 

 in the rock, and is that which gives to it its characteristic peculiarities. 



- ni the eleolite-syenite, sometimes containing cancrinit ■ and al other times rich in 

 sodalite, may also be found in almost any of the stone walls dividing tin/ fields that lie within an 

 area encompassed by lines joining (lie above described points. 



j-These zircons were analyz :d by Gibbs (Pogg. Annalen, b. Ixxi. 1822, p. 559) with the following 

 result: Si0 3 = 35.26; Zr0 2 = 63.33; Fe»0 3 = .79; undet. = .36. 



I Ain. Jour. Sci., 3d ser., vol. xxxi, 1886, ]>. 'jnS. 



