The Composition of Peat, and Ecological Methods. 171 
composition! Both samples were of a pasty consistency 
when obtained and it is certain that the water percentage is 
approaching the limit of what may be termed ‘ solid’ peat ; 
a further increase of this constituent would undoubtedly con- 
stitute ‘ bog’ or ‘swamp’ condition. 
RisHwortH Moors. CALDER VALLEY (Dean Head). 
Parts per cent. Parts per cent. 
Moisture = 85:2 (Moisture-free 84°85 (Moisture-free 
*Organic and peat). peat). 
Volatile Matter 14°35 96:96 (‘Humus’) 14:60 96°37 
Ash .. . "45 3°04 *55 3°63 
100-00 100-00 T0000 100-00 
*Containing 
Nitrogen +173 7 “172 Tm 
VON? | 71: -098 “06 55 3°63 
< Water content 
Ratio 499 pts. dry peat S75 575 
Peat usually contains 80-go per cent. of moisture and when 
air dried, 15 to 25 per cent.; the organic and volatile matter 
of the moisture free residue contains 50 to 64 per cent. of carbon, 
4:5 to 6'8 per cent. of Hydrogen, 28-0 to 44-0 per cent. of Oxygen 
and -5 to 2-5 per cent. of Nitrogen. The moisture-free peat 
also contains a fairly large and variable amount of mineral 
matter, 3 to 15 per cent. or more. The ash, unlike that of 
wood, is not alkaline, and is usually infusible ; its composition 
also varies considerably, sulphates and carbonates of lime and 
magnesia, ferric oxide and silica being usually the most pro- 
minent constituents. 
The 80 to go per cent. of moisture in peat is very difficult to 
deal with, and cannot be got rid of by pressure. The reason 
for this is that ‘ peat substance’ consists of vegetable debris, 
the cells of which contain and are surrounded by a slimy 
‘hydrocellulose ’ formed by the prolonged contact of the original 
cellulose with water. Although this constituent is present to 
the-extent of 0-2 to 1-2 per cent. only, it is in the form of an 
enormously swollen jelly of the constituency of soft-soap, and 
contains as much as 25 times its own weight of water. When 
submitted to pressure it may be forced through the interstices 
of stout canvas quite unchanged. It is, however, rapidly 
hydrolysed by water at 150° to 200°C., forming the solvble 
dextrose, and after such treatment the peat readily parts with 
its water under pressure. 
From a comparison of these two accounts of the com- 
position of peat, one must conclude that in Ecology, as in other 
studies, there are those who perhaps, becoming over zealous for 
the cause, give aberrant accounts of well-known facts, so that 
to the ordinary individual there is still occasional need of ‘ Lux 
in tenebris * in matters ecological. 
1913 April r. 
