ACKROYD : OX THE CIRCULATION OF SALT. 
403 
The reservoir water was fairly constant with an average of ri88 
parts of chlorine per 100,000. This figure will be greater than that 
of the annual average rainfall on account of evaporation, and if we 
deduct 10 per cent, it would still be equivalent to a fall of 172 lbs. 
of common salt per acre with the 1899 rainfall of 43-17 in. 
The rain-gauge figures fluctuated wildly. Widdop rain-gauge 
water reached o'.') per 100,000 during a December week when a 
violent storm was blowing from the Irish Sea about 40 miles away, 
and on another occasion it got up to (ro. The average for the 14 
weeks of observation was 1'50. That the winter average should 
be in excess of the yearly average is in keeping with the results obtained 
by other observers, and gives some idea of the activity of salt circu- 
lation during the stormy part of the year when gales are prevalent 
from the sea. The abnormally high figures obtained at Widdop 
synchronised with similarly high figures for the other gathering 
grounds ; this is well seen in the plotted curves for the rain-gauge 
results. (Plate LXYIl., fig. 2.) 
Observations on chlorine in rain-water have been made at Ciren- 
cester since IS 70 by Professors Church, Prevost, and Kincli.* An 
abnormal amount of chlorine has almost always been traced by them 
to salt spray from the Bristol Channel 35 miles away. On different 
occasions immediately after a storm from the S.W. crystals of common 
salt have been found on the College windows facing west. The same 
kind of evidence lias been furnished to me by Mr. J. H. Howarth 
respecting Mai ham ; concerning Leeds by ^Ir. J. E. Bedford, and 
Mr. J. Denison calls my attention to the following references : " The 
winds from the South-West have sometimes blown so strong that the 
pieces of cloth on the tenters in several parts of Halifax parish have 
been charged with a considerable number of saline particles brought 
from the sea,"t and further, " Sea-salts have been found deposited 
on the windows in West Park and York Place. Harrogate, thus giving 
practical evidence of the presence of the sea-breeze. "J 
' Tians. Chem. Soc, Vol. 77, p. 1271. 
t Watson's Histon- of Halifax, 1775, p. 5. 
J The Use and .Vbiise of Harrogate Mineral Waters, by Arthur Roberts, 
p. 32. 
