1894] Geology and Paleontology. 159 
the mean slope-angle being 20°. The southern boundary of the moun- 
tain is the nearly east and west valley through which runs the Central 
New England and Western Railroad. On the northwest Mt. Wash- 
ington is merged into the narrow ridge of the Taconics, which extends 
northward into Vermont. The name, Mt. Washington, however, ap- 
plies properly to all of the range lying south of the South Egremont- 
Hillsdale turnpike. The regular elliptical contour of the mass is 
broken oni the northeast by two deep embayments, the eastern one con- 
taining Fenton Brook, and the western, which is knee-shaped, being 
occupied by Sky Farm Brook. The regularity of contour is further 
interrupted by an outjutting spur on the west side, known as Cook’s 
Hill. South of the topographical break which limits the mountain in 
the neighborhood of Ore Hill, the range of the Taconics pursues a 
more interrupted course, the hills becoming smaller and spreading out 
considerably.” 
In the account of his investigations the author states that a micros- 
copic examination of thin sections of rocks from Mt. Washington 
shows clearly that they are strongly metamorphosed clastics. Evi- 
dence has been deduced from the secondary growths of feldspars, gar- 
nets and tourmalines, as well as from the relations of the different met- 
amorphic minerals to one another, to show that the orographie forces 
to which these minerals owe their development, operated in several 
more or less distinct periods. 
What is set forth in the paper agrees with Professor Dana’s views so 
far as the northern portion of the area is concerned. It is in regard 
to the southern and central portions that different views are enter- 
tained. Mr. Hobbs attributes this difference, not to errors in Professor 
Dana’s observations, for in the main they have been confirmed, but to 
the collection of a larger number of observations and to the applica- 
tion of some structural principles which were not made use of by Pro- 
fessor Dana. 
_ In conclusion Mr. Hobbs gives the following summary of the results 
discussed in the paper: ` 
“The Mt. Washington series consists of four members which, in 
order of age are as follows: (1) Canaan Dolomite, (2),Riga Schist, (3) 
Egremont Limestone, and (4) Everett Schist. A somewhat striking 
lithological distinction is found to separate the two schist horizons, the, 
Everett shist being entirely free from garnet and staurolite, while the 
Riga shist usually (not always) contains macroscopic crystals of one 
or both. The older rocks are found in the southern portion of the. 
atea, a general northerly pitch carrying them successively below the 
