MAINE. 
177 
lacial clays are abundant in the vicinity of the limestone, and it is 
robable that some of these clays can be found of suitable composition 
or a Portland-cement mixture. The Knox County limestones are 
f very satisfactory composition as cement materials, as is shown by 
he analyses quoted below. 
Analyses of limestones from Knox Count;/, Maine. 
ilica (Si0 2 ) L. 08 
lumina (Al.,0.) - 07 
ron oxide ( Fe 2 3 ) 08 
ime carbonate (CaC0 3 ) 98. 1 7 
Eagnesium carbonate ( MgC0 3 ) .09 
ivater n. d. 
1.00 
0. 43 
.71 
Trace. 
.25 
95. 20 
97. 69 
1.00 
.82 
2.70 
n. d. 
1. McNamara quarry, Rockland. J. C. Robinson, analyst. Twentieth Ann. Rept. U. S. Geo!. Sur- 
y, pt. 6, p. 398. 
I. Bachelder quarry, Union. J. C Robinson, analyst. Ibid. 
3. Rockland-Roekport Lime Company. Communicated by G. O. Smith, 1904. 
Limestone beds of considerable extent also occur near Islesboro. 
specimen from this locality, collected b}^ G. O. Smith, was analyzed 
y W. T. Schaller in the laboratory of the United States Geological 
urvey, and proved to be a very pure limestone, low in magnesia. 
Analysis of limestone from Islesboro, Me. 
lica (Si0 2 ) 3. 76 
lumina ( A1 2 3 ) 1. 03 
■on oxide (Fe 2 3 ) 43 
ime (CaO) 51. 30 
agnesia (MgO) 1. 16 
The following analysis, communicated by G. O. Smith, is of a clay 
3curring on the property of the Rockland-Roekport Lime Company, 
i Knox County. As can be seen from the analysis, it would serve 
ell to mix with the limestones above noted: 
Analysis of clay from Knox Conn/;/, Me. 
lica (Si0 2 ) 61. 59 
lumina (A1 2 3 ) 19. 10 
on oxide ( Fe 2 3 ) 7. 53 
me (CaO) 1.68 
agnesia (MgO) 1. 87 
irbon dioxide (C0 2 ) •» r _ 1 
ater / 
The analyses of limestones given in the following table are quoted 
•oni an early report, by Professor Hitchcock, on the geology of 
aine. They are inserted here, as they may serve to some extent as 
Bull. 243—05 12 
