304 
FLORIDA GEOLOGICAL SURVEY—THIRD ANNUAL REPORT. 
7. Mangrove peat from along east side of Snake Creek, which 
is the channel between Windly’s Island and Planiation Key (or 
Long Island), Monroe County, near 437 mile-post on Florida East 
Coast Ry. Taken from about 3 feet below the surface, in man¬ 
grove swamp, whose vegetation is mostly Rhizophora Mangle (red 
mangrove). Peat reddish brown, very coarse and fibrous. Col¬ 
lected in September, 1910, under direction of W. J. Krome, Con¬ 
structing Engineer of the F. E. C. Ry. Extension, at our request. 
Analysis by E. Peck Greene, assistant state chemist. 
No. 
Moisture 
in 511 r- 
ABSOLUTELY DRY PEAT. 
111 ctii 
dry peat 
Ash 
Fixed 
carbon 
Volatile 
matter 
Sulphur 
Nitrogen 
Fuel value 
(B. T. U.) 
1 
2 - 
17.2 
8.3 
14.7 
30.1 
30.7 
61.6 
54.6 
.59 
4.08 
2.89 
1.93 
10082 
8816 
3 
18.0 
29.9 
52.0 
3.94 
1.97 
8586 
4 
25.7 
25.9 
48.4 
3.64 
1 .66 
7783 
5 
16.6 
30.8 
52.6 
4.13 
1.94 
8705 
6 
7 
10.0 
16.0 
11.0 
15.2 
26.1 
62.8 
.39 
2.74 
2.36 
(9877) 
|] 
NOTES ON THE SIGNIFICANCE OF SOME OF THE ANALYSES. 
It would seem from the figures given that most of our peat 
contains only about half as much water when air-dry as does the 
better known material from the glaciated region of Europe and the 
northern parts of this continent. Too much stress should not be 
laid on this, however, for the water-content shown probably depends 
nearly as much on the condition of the air at Pittsburgh at the time 
the analyses were being made as it does on the nature of the peat 
itself. (All the samples which show more than 10% of water 
were collected in April, May or June, and analyzed a month or 
two later, when the air of the room in which the tests were made 
was presumably more humid than in winter, on account of artificial 
heat not being used.) Nevertheless, it is probably safe to say that 
the Florida peat dries out as well as that from any other part of 
the world, if not better. 
The purest peat is No. 29.11, which has only 1.5% of ash. 
Other samples with less than 5% are Nos. 13.11, 15.11, 29.12, 
37.11, 41.11 and 42.11, all of which are from peat prairies or 
similar situations. (Locality No: 37 I have called a tyty bay, but 
it is treeless in the middle, and therefore has the characters of a 
peat prairie). 
The proportion of volatile matter to fixed carbon is nearly 3 to 1 
in No. 19.11, a coarse saw-grass peat. In nearly every case 
