18 
lowing to shew what difficulties such a project has to en¬ 
counter. 
Having examined all the passes, he made choice of the route 
commencing at the little Bay of Vaca de Monte 20 Kilo¬ 
metres (12 miles) west of Panama, he makes it 54f Kilo¬ 
metres (34 miles) to the river Chagres; passing over the gap 
of Ahogayegua 140 metres (or 460 feet) above the sea level; 
and continuing 9^ Kilometres (5j miles) in the bed of the 
Chagres as far as Gatun, he then goes direct to the Bay of 
Limon a distance of \2\ Kilometres (7f miles) being a total of 
76 Kilometres (47-J- miles) from sea to sea. 
Mr. Garella admits the impossibility of any supply of water 
being conveyed to the summit level of the gap of Ahogayegua 
though it be no more than 140 metres (460 feet) high. The 
greatest height to which water could be conveyed by trenches is 
41 metres (131 feet). 
This suggests the necessity of adopting one or other of the 
following plans. Either to make an open cutting at the gap 
of Ahogayegua to the level to which water can be conducted 
which would require locks for every 3 metres of height—there 
would be on one side lockage for 48 metres, and on the other 
54 metres, on account of the difference of tides in the two 
oceans. Or to pierce a tunnel at the same elevation, of dimen¬ 
sions sufficient to let ships of 1200 tons burthen pass through 
with their lower masts standing ! of these two projects Mr. 
Garella inclines to the latter if the public could at all be led 
to contemplate the possibility of its execution. And these are 
the dimensions he deems sufficient for the object. 
Height from the bottom of Canal to crown of the Arch 37 metres (122 feet.) 
Breadth.21 „ ( 69 feet.) 
Total length 5350 metres or 5900 yards. 
This would further require approaches of open cuttings 45 
to 50 metres deep (165 feet). 
This tunnel M. Garella thinks would be cut through a solid 
rock of porphyry therefore probably not exposed to the chance 
of falling in and possibly requiring little or no masonry. 
However, allowing that this last might cost 14 millions of 
