Dromon and Drakkar, Oars at War.
Gordon S Fowkes, KCTJ
Both Viking ship and
Mediterranean Galley played major roles in the Crusade as together they gained
a few centuries of naval and maritime superiority until the Ottomans picked up
where the Arabs had left. These war
vessels were often modified and expanded for commercial purposes and
complemented the rise of the short fat sailing ships that was the life blood of
the 12th Century Renaissance. They represented two distinct design
and construction plans but which intermingled and married in the shipyards
north and south.
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Drakkar (Longship) and Dromon (Galley)
The Viking Long Ship
was an exceptional sailing ship, with good to excellent rowing capabilities. It was not long before Viking ships were
shortened, the deck in place, and oars were stowed. The Dromon was the standard Byzantine warship
in the Mediterranean which became the warship of choice for all colors and
creeds well into the gunpowder age. Both
ships were fast under oars and while it is now accepted that Dromons and other
Medieval galleys were rowed with the oarsmen standing up. Since the Vikings and Byzantines fought with
and against each other including service on Dromons against Byzantium’s
enemies, it is more than likely that rowing tips and ship design intermingled.
These ships had a
high length to width ration in excess of seven to one. Even as high as ten to one. This high ratio plus the low angle the oars
had to have lowered the freeboard to the point that rowing in rough waters was
pointless. The distance between rowing
station (tholes, benches, thwarts, oars) on Viking ships was 32 inches, while
on the Dromon it was a foot longer.
Therefore there is likely a wide variety of rowing techniques. The paper Is
intended to muddy the differences.
Crusade Era crews
were made up of free men already organized in fraternal, commercial, and
military roles. In fact the use of
galley slaves is a rare exception in history and unsatisfactory when used. The
collective skill sets required of oarsmen as shown here requires drill team
precision and football ardor
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The Boat Races
1959, I was a
coxswain on the University of California (Berkeley) Crew, then consisting of
the 8-oared shell. That’s the little guy
at the back (aft) of the boat with a big mouth with eight really big guys on
the oars. We used to race up and down
the Alameda estuary for races and practice.
In order to see what
these ships and crews were capable of, one can look at You Tube:
“Holy Smokes, they
are flying!” An eight oared shell
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Modern racing shells
(solo to eight oars) use seats that slide, and so far as we know today, rowing
seats had to wait the 19th Century.
More than likely.
Imagine one of those
dromons with as many as a hundred oarsmen would look like in a final drive to
close with the enemy.
BALANCE OF POWER
The “balance of
power” of the oarsmen exerted between port and starboard, and between fore and
aft is critical or the ship will heel and wobble.
Angles of Oars to Water.
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In order to get
maximum power between the oar and the water, the angle must be very low. This was a major design feature of all
galleys and Viking ships which also produced a very low distance between gunnel
and water. This made sailing any long
and low ship in troubled waters short and wet. As a consequence oar powered
vessels avoided rough water, hugged the shoreline and came on shore for bad
weather and/or night.
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The Galleys of the
Mediterranean (later large galleys were used in the Wool trade to reach
northern waters were built frame first.
They, like the Romans and Greeks before, drove through the waver rather
than over. Unlike them, the ram had been removed and replaced with a prow. The tactics changed from ramming to boarding.
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The Viking Long Ship was clinker built (hull
built before framing), and had good sea keeping capabilities as it could bent
and twist in rough seas. Since the water
far at sea was likely to have higher waves than on rivers, Viking traders and
raiders shortened the length to width ratio to under five to one. This modification together with decking the
thwarts and relying on sail is what is depicted in the arts of the time. They could not have raided across the North
Sea to the Bosporus with a ship too long.
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Therein lies the
mystery, which is where were the oarsman’s hands, feet and fanny relative to
the gunnel, oar, thwart and thole (oarlock).
The purpose of this article is to let in more dark to confuse
certainty. The short answer is that more
serious rowing required standing, not sitting.
But more before that:
Oars vs Rudder
If the power of the
port (left) is greater than starboard (right), the ship will turn to the right
(starboard). This requires the helmsman
to steer to port (left) which throws the ship off balance, by leaning away from
the turn; the ship rocks to the outside
of the turn which further unbalances the ship.
Been there, done that.
The selection and
placement of oarsmen and their oars with a mix of the skinny, round, tall and
short to keep that balance is essential.
While in modern rowing, the person has to fit in the boat, while that
choice was not as popular back then.
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Recovered oars at the
same site often differ in length. Some
plans and pictures of the multi-decked ships show the outboard oarsmen with the
shorter oar rowing closer to the hull.
More common are the images of two or more banks of oars, regardless of
number of oarsmen per oar, having all blades paddle in the same row of puddles.
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Most oar ships of the
day normally had a flat deck from bow to stern, but not always. Some ships placed the higher benches and
longer oars towards the stern. In order
for the oars to synchronize, the bow oars (men) were shorter with the taller
and longer, the higher. It also provided a commanding view of the crew for
those on high. That and the guys closest
to the boss are tall by mutual assent.
When I was a private
(E-2) short in stature I marched in the rear, and as is the effect of short
last, the column marched like an accordion with the short on the run. When I was a Captain commanding an Engineer
Company, the tall came last, and the formation got short. On the galleys of the day, the short came first,
albeit backward.
Gearing Ratio
The relative length
and gearing ratio (balance) between handle, thole (oarlock) and blade affects
the amount of leverage the oarsman can exert in pulling the boat across the
water. The ratio of oar inside the ship
versus outside, defined by the location of the thole (hole, oarlock) as a
fulcrum. In the Medieval Era, that
ration ranged between 1:3 (one third inside) and 1:4 (one quarter inside). 1:3 favors getting underway faster, while
1:4 favors speed once underway.
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Catch and Release
All oars must enter
and leave the water exactly the same time and angle cleanly to retain the
balance of power. Splashing slows the
boat and the race is won on the run, not the drive. In short when the oars are out of the water. Catching occurs when the oar goes into the
water, and the release….
10
The oars today are
feathered on the run in order to evade snagging the blade on the water (ripples
and waves). This reduces how much the
oarsman has to raise the blade/lower the wrists on the run versus lowering the
blade/raising the wrist. This distance
must be changed as the seas get rougher.
In modern racing
boats, this is all in the wrists. No
kidding. The blade is turned by rotating
the oars forward for the catch and back for the release. The latter uses the rush of water to flip the
oars out of the waters, in lieu of yanking against the water.
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The historical
evidence supporting this use of the wrists to make a clean catch and release is
indicated by this old piece of statuary.
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The Run
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The Perfect Stroke
(Boston)
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The race is won on
the run not the drive. A sloppy but
powerful crew will be beaten by a precise albeit weaker crew.
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The essential difference between modern crew
rowing and of the good old days is that today the oarsmen (oarswomen) is the modern
sliding seat which allows full extension of the legs. Since the upper body has about a third as
much power as the whole body, the big mystery in scholarly studies of rowing
has been to ignore that the legs were used in rowing in order to go faster than
the other guys. Be they close ahead or astern.
Stand and Row
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The short answer is that back then they stood and rowed, stepping
forward to plant a foot or two against a load bearing member of the ship. Those include other benches or steps for the
purpose. The only time these oarsmen rowed sitting down was in port. This particular
example is of a chained oarsman. At best
this shows that standing and rowing was not sitting down.
Later rowing systems
based on Italian designs including rowing arrangement of more than one oar to a
station, and/or more than one oarsman to an oar. Crusade Era ships were one and one.
.
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These diagrams show
illustrate the difference in height relative to rowing stand up or sitting. It
is about 3 feet from the deck to the elbows and if sitting.
The basic issue of
whether to stand or sit relates to the skeleton and muscular makeup of the
body. The sliding seat likely did not
exist, and the amount of stroke an oarsperson sitting down is less than one
standing up and moving. Key to this is the difference between seats whether
bench or thwart (longitudinally)
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The best ballpark figures I have, show that
the distance between thwarts, tholes (oar locks) and oars on Viking ship are
about 32 inches (.8 meters) and those on the Galleys were 47 inches (1.2
meters). The oars and tholes in Viking ships were exactly half way between
thwarts, with the shield even with the thwart.
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21
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Load Bearing Members Carry
the Load of the Members
There is stress
wherever the boat, the oar, the water and the oarsman meet and the net result
of this stress is a boat in a hurry. These
occur in a sequence from where the foot and the boat, butt and bench, oar and
thole, blade and water. Anything but the
strongest materials will cause the boat to stop running.
Leather padding or
gaskets reduced the friction of oar on thole.
Some galleys do not have a round thole but a peg or more between which
takes up the friction which allowed more than one oar to a thole.
A standing oarsman on
a Viking type ship such as the Knarr could get his weight and body strength stepping
on the thwart forward or the smaller one under that thwart. A galley oarsman normally had a step in front
of his bench which was also a load bearing member of the ship. This is what is shown in the Russian sample.
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Precision, Decision, and
Synchronization.
The subject of oaring
boats is huge, with larger variations of equipment and technique. This treatise shows only show a few
combinations. The drawing in Russian
drawing above is one of a ship rowed by slaves (note chain). The bulk or and primary choice of crews,
however, were professional crews of volunteers often chartered by the maritime
powers of the world. These ships and oarsmen were often rented out for cash,
alliance or privateering.
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