EB. B. Hunt on a new Sounding Apparatus. 
or if used as the reading fluid without mercury would be 
perhaps too sensitive. 
) 40, would be more manage- 
rpentine, sp. gray. = ‘991, would, if its fluidity suf 
_ ficed, be very good. Wine is = ‘992, and if it coul kept 
pure might do, though too little sensitive in fresh water. If we 
assume that 100 feet is our limit of depth to be sounded, we can 
readily proceed from this to fix the size of air-vessel required if 
ir is used, or the len i 
