CHAPTER IV. 
THE CANON OF LODORE. 
June 8. We enter the canon, and, until noon, find a succession of rap 
ids, over which our boats have to be taken. 
Here I must explain our method of proceeding at such places. The 
"Emma Dean" goes in advance; the other boats follow, in obedience to sig 
nals. When we approach a rapid, or what, on other rivers, would often be 
called a fall, I stand on deck to examine it, while the oarsmen back water, 
and we drift on as slowly as possible. If I can see a clear chute between 
the rocks, away we go ; but if the channel is beset entirely across, we signal 
the other boats, pull to land, and I walk along the shore for closer exami 
nation. If this reveals no clear channel, hard work begins. We drop the 
boats to the very head of the dangerous place, and let them over by lines, 
or make a portage, frequently carrying both boats and cargoes over the 
rocks, or, perhaps, only the cargoes, if it is safe to let the boats down. 
The waves caused by such falls in a river differ much from the waves 
of the sea. The water of an ocean wave merely rises and falls ; the form 
only passes on, and form chases form unceasingly. A body floating on 
such waves merely rises and sinks does not progress unless impelled by 
wind or some other power. But here, the water of the wave passes on, 
while the form remains. The waters plunge down ten or twenty feet, to the 
foot of a fall ; spring up again in a great wave ; then down and up, in a 
series of billows, that gradually disappear in the more quiet waters below ; 
but these waves are always there, and you can stand above and count them. 
A boat riding such, leaps and plunges along with great velocity. Now, 
the difficulty in riding over these falls, when the rocks are out of the way, 
is in the first wave at the foot. This will sometimes gather for a moment, 
heaping up higher and higher, until it breaks back. If the boat strikes it 
the instant after it breaks, she cuts through, and the mad breaker dashes its 
spray over the boat, and would wash us overboard did we not cling tight. 
