Introduction This article is remarkable in detailing Clarke's daring
and skill in surfing the wake of a large paddle-steamer on the
Hudson River, but also the a basic
explanation, with illustrations, of
the mechanics of wave riding.
Coasting in the Wake of a Ferry Boat
A Hudson River Modiﬁcation of a
Stealing a ride on the waves of a side-wheel ferry boat.
PASSENGERS crossing the Hudson River on
the ferry that runs from the foot of Dyckman Street, New
York, have been treated to
see the odd spectacle of a canoe sailing in their wake, all
the way across, without any apparent means of propulsion.
Only occasionally do the occupants of the canoe dip a paddle
into the water to steady the craft and keep it on its
What makes the canoe go, is a question that has puzzled many
Almost everyone knows that immediately behind a side-wheel
ferry boat there is suction or an inﬂow of water to ﬁll up
the gap left
by the vessel.
No doubt, most of the ferry passengers have attributed the
progress of the canoe to this cause, but the more observant
have noticed that the canoe does not keep to the
comparatively smooth water directly aft, but rides off to
one side in the rough waves that are kicked up by the paddle
wheels; also that the canoe does not hug the ferry boat
closely, but may pursue its mysterious course at a
considerable distance, while travelling just as fast as the
Sometimes the canoeist rides an eighth of a mile behind the
There is no hidden power plant in the canoe, and yet the how
wave that it makes as it speeds along shows that it is not
carried along on a current of water.
Another point to be noted is that the canoe always takes a
position on the forward side of a wave, and that it holds
this position all the way across.
This lets out the secret for it is the wave that carries the
canoe along, in the same way that the Hawaiian on his surf
board rides at high speed for half a mile or more on the
waves that roll shoreward.
This does not mean that a current of water carries him
forward, but that the waves do.
The tide may be setting out and yet if the waves roll
shoreward the surf board will go in on them despite the
outgoing tidal current, because it is the waves that push it
To illustrate the phenomenon, imagine a marble on a carpet.
If the carpet is wrinkled by pushing it forward with the toe
the marble will roll along ahead of the traveling wrinkle in
just the same way that the surf board glides along pushed by
the advancing waves.
Of course the surf board does not roll, but it is pushed
ahead just the same.
Perhaps a more apt comparison is presented in the
accompanyingsketch of a bottle and a
Lay a bottle on a table top and support one end of a ruler
Now if the bottle is rolled forward the ruler will slide
ahead, just as the marble did ahead of the wrinkle in the carpet. The same is true of the canoe, which is shown in the
The canoe stands in an inclined position on the side of the
As the wave advances to the position shown in dotted lines,
the canoe must advance also.
It cannot ride over the wave without running up hill and
consequently it must be pushed along by the wave.
The man who has been performing this interesting experiment
is Mr. C. H. Clark.
Occasionally he makes the trip alone but our photographs
show him accompanied by Miss Frances Ketchman.
Mr. Clark informs us that one of the ferry boats he follows,
makes a speed of about 12 miles per hour when under full
Directly back of the ferry boat there is a suction producing
a current of about two miles per hour in the direction in
which the boat is traveling.
The void back of the ferry boat is largely ﬁlled up by water
ﬂowing in from
Back of each paddle-wheel there is a current in the opposite direction, of about three miles
The waves are produced by the water lifted up by the paddles
above the normal level.
The water then drops and continues to oscillate up and down.
Right at the paddles there is also a quantity of water that
is being lifted up.
In other words there is always a wave crest at the paddle
wheels so that the waves which are formed always travel in
direction as the ferry boat travels and at precisely the
same speed, as long as the paddle wheels are running.
Although there is this forward motion of the waves at 12
miles per hour, there is a rearward current of three miles
per hour, so that the canoe which travels on the waves must
actually go through the water at 15 miles per hour, as long
as it keeps up with the boat.
It seems odd that the canoe can overcome this rearward ﬂow,
but the action will be clearly understood if we refer again
to the marble on the carpet.
Suppose that the wrinkle is produced by a. ruler that is
moved along under the carpet and that while the ruler is
moving forward the carpet is being drawn rearward.
The marble will still continue to slide forward ahead of the
This is exactly what the canoe does.
There is not enough rearward current to carry it uphill over
the crest of the waves and as long as the craft lies on the
forward side of the wave it must progress with the wave and
at the same speed as the wave. matter of fact the rearward
current helps to maintain the canoe on the side of the wave
and to prevent it from burying its nose in the trough of the
All that Mr. Clark has to do is to paddle his canoe to the
proper position on the wave that he selects and then he may
fold his arms and lot the ferry waves carry him across.
It is a surprising fact that he usually beats the ferry
across, because when the ferry slows up the paddle wheels
act as brakes and the waves which they have set up travel
ahead of the boat carrying the canoe along with them.
Although the occupants of the canoe like to indulge in feats
of daring such as standing up in the light craft, as shown
in our illustrations and performing various stunts, yet
riding ferry boat waves calls for a . considerable degree of
skill and should not be attempted by any one but a strong
One of the pictures shows some of the dangers that are
encountered in a much traveled waterway such as the Hudson
River there are apt to be cross currents which disturb
of the canoeists riding the waves thrown up by the
paddle-wheels of a ferry boat.
In the picture
above note the side
slap at the bow, one of the dangers of this sport.
The picture at the left
shows the canoeists riding well
to the rear of the ferryhoat.
the right they are shown comfortably
seated on the side of a wave.
on this page by Edwin Levick.
the smoothness of the waves.
There may be a side slap on the bow of the canoe that will
throw it of its course, turn it around in the trough of
the waves and upset it.
The canoeist. must be constantly on his guard to avert any
Mr. Clark makes the interesting suggestion that in towing
a small boat behind a vessel that is throwing up a
considerable wave it is advisable to draw the boat to such
position that it lies on the forward face of the wave
instead of in the rear face of the wave, so that the wave
will push the boat along and there will be scarcely any
strain on the towing line.
Experiment with a
ruler an a bottle, showing how the wave pushes the