182 
TATE: SOURCE OF RIVER AIRE. 
and formed a stream which by a few minutes after five o'clock 
was fully a hundred and fifty yards long. At 5.25, one hour 
and twenty-five minutes after leaving the Tarn, the water 
began to creep over the half-submerged pebbles at Airehead 
Springs. At 5.50 the depth, at its junction with the Aire, 
had increased from 8 J inches, at which it had stood all day, 
to 12f inches ; so that in 25 minutes a stream 4 feet wide 
had deepened 4J inches. 
The explorers then adjourned for dinner, when it was 
reported that up to 5.45 p.m. no change had been observed 
at Malham Cove. On returning to the Cove, however, the 
scale indicated a rise in the meantime of 2 inches in a stream 
31 i feet wide. By the same time the stream at Airehead 
had risen nearly a foot. Wo chaff had as yet made its appear- 
ance ; therefore nets were drawn across the streams at suit- 
able points to intercept any that might be floated out during 
the night. At 10 p.m. the Tarn sluices were again closed, 
all but about an inch or so, to keep the fish down stream alive. 
Second Bay. — Wind N.E. JNo chaff in any of the nets. 
The water, both at the Cove and Airehead, had fallen to its 
normal level. At 11 a.m. an attempt was made to stain the 
water at the Smelt Mills by the introduction of a quantity of 
magenta ; but a preliminary trial in the open stream was not 
very promising, all trace of the aniline disappearing in a 
distance of seven or eight yards. At 11.30 bran was put 
into all the Tarn " watersinks." A preliminary trial, in this 
case also, was far from encouraging. At twenty yards the 
bran was distinctly seen floating in the open stream ; at forty 
yards not a trace could be perceived. It was found to have 
sunk to the bottom waterlogged. At 1 p.m. the Tarn sluices 
were again raised, and the liberated water reached the sinks 
at 1.25, being seven minutes longer than on the previous 
day. This was owing to the diminished volume of the stream 
between the Tarn and the sinks. A rise in the water level 
