374 Observations on an 
surface of it rising and falling alternately in 
a manner which he could not explain, by sup 
posing some slight irregularity in the manage- 
ment of the pump. When the appearance 
was more carefully examined, he found a 
corresponding variation in the efflux at the 
nozle; for when the water was rising in the 
tub, the stream was perceptibly weaker at 
this outlet, than it was during the ebb or fall 
of the water in the vessel last mentioned. 
He farther observed, that when the water in 
the boiler rose high enough to cover the end or 
nozle of the siphon, bubbles of air were seen 
ascending from this orifice, during the ebb 
in the tub, or at least during the former part 
of it; but that they did not appear during the 
flow, or whilst the water was accumulating 
in the tub. The fluctuations here described, 
were far from being regular, either in magni- 
tude or duration; for the water rose much 
higher in the tub at one time, than it did 
‘at another ; and the intervals betwixt flow 
and flow, or ebb and ebb, were very unequal. 
In fact the appearances seen in this vessel 
imitated the caprices and singularities of Gig~ — 
gleswick Well in a natural and. surprising 
manner. 
The exact coincidence of the effects, pro- 
duced by an artificial apparatus, and a noted 
