eckel.]  PORTLAND-CEMENT    RESOURCES    OF    NEW     YORK. 
527 
COMPOSITION. 
The  composition  of  the  Helderberg  limestone  is  shown  by  the  Hol- 
lowing analyses: 
Analyses  of  Helderberg  limestones,  New  York. 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
L6 
17 
18 
111 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 
Silica 
(SiOo). 
Alumina 
(AI0O3). 
Iron  oxide 
(Fe2Os). 
0.64 
.60 
3.16 
7.18 
.7 
1.64 
.36 
n.d. 
n.d. 
n.d. 
1.50 
.95 
1 .  55 
1.55 
2.14 
1.35 
1.38 
.30 
.48  I 
97 
n.d. 
n.d. 
6.66 
1.45 
3.35 
.63 
1.01 
1.50 
2.  50 
1.07 
1.34 
1.57 
n.d. 
n.d. 
n.d. 
.  53 
n.d. 
n.d. 
.99 
.74 
1.15 
1.82 
.  55 
1.6 
1.65 
1.34 
Lime 
(CaO). 
54. 06 
51.78 
49.70 
40.23 
54.32 
48.68 
52.53 
35.25 
43.  22 
48.82 
50.25 
53.  52 
50. 47 
52.69 
50.25 
50.80 
50.  93 
50.  06 
51.82 
51.05 
53.62 
52.46 
44.72 
48. 34 
44.27 
54. 51 
51.  K) 
51.35 
53. 10 
45. 22 
54. 1 1 
Magnesia 
(MgO). 
0.48 
.88 
1.44 
1.95 
.53 
1.84 
.69 
8.94 
6.08 
1.48 
1.00 
.46 
.83 
.84 
1.11 
1 .  01 
.  85 
2.  74 
I.  16 
1 .  65 
n.  d. 
n.d. 
1.98 
2.93 
3.17 
.66 
2.23 
1.67 
n.  d. 
Trace. 
Trace. 
Carbon  di- 
oxide (CO.). 
1.  Fogelsonger   quarry,    Williamsville,    Erie   County.      II.    Carlson,    analyst.     Twentieth 
Ann.  Rept.  U.  S.  Geol.  Survey,  pt.  (>,  p.  427. 
2.  Howells  quarry,  Leroy,  Genesee  County.     Bull.  New  York  State  Mus., 
3.  Strobel  quarry,  Leroy,  Genesee  County.     Ibid. 
4.  Babcock  quarry,  Waterloo,  Seneca  County.      Ibid.,  p.  8.19. 
5.  Alvord    quarry,    Jamesville,    Onondaga    County.      P.    E.    Engelhardt.    analyst, 
p.  806. 
No.  44.  p.  784. 
Ibid. 
