36 THE FRESH-WATER LOCHS OF SCOTLAND 
or less sensitive by increasing or diminishing the diameter of the well. 
By merely tm^ning the stopcock, and shutting off the communication 
with the well, we turn the instrument into a very sensitive barometer. 
The curve which it traces is thus changed, at a moment's notice, from 
a limnogram into a barogram, so that we can alternately record the 
Fio. 11. 
denivellation of the lake and the variation of the atmospheric pressure. 
If, instead of closing the stopcock C, it is left open, and the other 
end of the tube CC allowed to communicate with the open air through 
a capillary tube of properly chosen length and bore, the statoscope 
will act exactlv like the Dines-Shaw microbarograph, with the 
advantage of a larger time-scale. The instrument itself I call a 
s tatoli m n ogr aph . 
