146 VEGETATION OF THE PEAK DISTRICT [CH. 
the Peak District, it is easy to distinguish the vegetation of 
the streams which flow over the non-calcareous or siliceous 
soils and which have a very low mineral content from that of 
the streams which flow over the calcareous soils and which 
have a high mineral content. 
Non-CALCAREOUS WATERS 
The late Mr Ackroyd (1899: 120), formerly the Borough 
Analyst of Halifax, has published figures giving the composition 
of the waters of a reservoir supplying that town; and this 
analysis is useful as it is typical of the whole of the non- 
calcareous waters of the sandstones and shales of the Pennines, 
including the Peak District. “The matters dissolved consist 
of mere traces of inorganic bodies, and a small amount of 
peaty acid....These waters are very soft, ranging from two to 
three Clark’s degrees'; and the hardness is of a permanent 
character?, 7.¢., it is not appreciably lessened on boiling.” The 
following is Mr Ackroyd’s full analysis :— 
Grains per Grams?® per 
gallon litre 
Total solids in solution ~ 0°075 
Total solids in suspension nil 
Chlorine, calculated as NaCl 0:019 
Iron, calculated as Fe,03 0004 
Sulphate of lime (CaSQ,) 0-006 
Free and albuminoid ammonia (NHs3) nil 
Acidity, calculated to its equivalent of 
sulphuric acid (H2SO,) 
Hardness =3 degrees (Clark’s)! 
Swamps (OR MARSHES) ON THE SANDSTONES AND SHALES 
The larger streams of the district have their sources on 
the peat moors, the smaller ones on the hill slopes. In the 
former case, the sources of the streams occur either in the 
1 A Clark’s degree is one grain of carbonate of lime (CaCOs) per gallon, or 
its equivalent of other lime (calcium) compound. 
2 Permanent hardness of water is due to sulphate of lime (CaSO,), tem- 
porary hardness to carbonate of lime (CaCO,). 
8 15°43 grains=1 gram; 0°22 gallons=1 litre. 
