508 
secretary's report. 
'■ This was done at 2 p.m. on Xovember 11th, and before 7 a.m. 
on the l'2th the water of the large spring at the reservoir in the Greta 
Valley was strongly coloured. 
" After introducing the fluorescein a general survey was made 
of the direction of the joints in the limestone in the neighbourhood 
of the sink and on the clints above Crina Bottom., with the following 
results : — 
Joint at ' sink ' N. 55° \Y. 
On ' clints ' near sink . . . . . . X. 55° W, 
On ' clints ' above and to the west of . . (main) N. 50° W. 
Crina Bottom . . . . . . . . (secondary) S. 25." W. 
" The spring at the reservoir is thrown out close to the line of 
junction of the Carboniferous Limestone with the underlying Silurian 
rocks, and the line from the sink where the fluorescein was intro- 
duced to the spring runs N. 55' W.^ — that is. in the direction of the 
master joints in the limestone. 
Thus, again, it has been demonstrated that the direction of 
underground flow is determined by that of the master joints in the 
limestone. 
" After a considerable though unavoidable delay, the work was 
resumed on June 21st, 1901, when Alum Pot. on the Ribblesdale 
side of Ingleborough, was the scene of operations. 
" The joints in the neighbourhood of Alum Pot are more com- 
plicated than in the parts of the district previously investigated, 
there being three sets of joints, all more or less irregular in places. 
'■ Close to Alum Pot there are two sets running S. 5° W. and N. 
80° E. respectively. 
" Thirty yards higher up Alum Pot Beck they run due X. and S. 
and N. 80° E.. the north and south joints being the stronger and more 
continuous. 
On the ' clints ' 100 yards above the Pot there are three sets 
of joints, as follows, viz. — 
One pound of fluorescein was put into the stream flowing into 
Alum Pot on Friday, June 21st, at 7 p.m. 
Master 
N. 10° E. 
Secondarv 
