First addendum to Inca's sail powered Balsa Log Raft
Observations from Egyptian tombs and pyramids
Handling a Thor Heyerdahl theme as Kon-tiki, we inevitable - by his reed boats RA, RA2 and TIGRIS - are brought in contact with the ship-lore of ancient Egypt.
Per Aspera ad Astra
Thor Heyerdahl was a researcher and investigator - and most of all an inspirator - and on his way he probably has tried many things - and learned.
Among the above 4 photos, specially two photos call our attention.
We observe that Kon-tiki still has a mizzensail. Such a sail is not useful for downwind sailing, and perhaps therefore it disappeared later.
RA2 shows up with two sidemounted Guaras in port bow. Those too disappeared later of same reason as the mizzen from Kon-tiki - not useful for downwind sailing.
Both the RA boats ware equipped with fixed mounted steer-oars aft, as give the needed hold back by downwind; but even those looked like the Egyptians, the RA steer-oars only could work twisting as a rudder and not by dipping - nor was it fastened to tilt, if digging into the shallow muddy river bottom.
A shallow muddy river bottom was more an actual risk for the later Tigris, as sailed on rivers, but nobody today knows how Tigris was equipped - she is pyred.
The observation of the Guaras on RA2 as start-equipment, the very same Kon-tiki museum neither knew nor had been aware, even having the old RA2 in keeping.
We must say, that it perhaps isn't important, what Thor Heyerdahl did, nor how he learned - the important is what the oldtimers did! But a photo is a photo, as is showing the things as they really ware at that moment, and not as they should be or could be. The originality of this RA2 photo is verified by the signs of 8 crew members.
Thor Heyerdahl's reed boats
I have no idea if the reed boats of Thor Heyerdahl were a copy of something.
Even if the master model for his reed boat is told to come from the Upper Nile of Sudan - it looks more like an expandet Titicaca-raft original from South America.
What is important here is, that the system of double steer-oar looks like the oldtimers from Egypt - apart form the fact, that the steer-oars at RA2 ware mounted with tillers as we can't see on the old paintings. On his RA boats, Heyerdahl could only twist his steer oar - but nevermind - who knows - on Kon-tiki Heyerdahl too discovered his Guara-steering under his raid. He learned.
Ra1 and Ra2
Thor Heyerdahl sailed mainly his RA boats downwind when crossing the ocean, and his reed boat was perfectly prepared for wind astern.
As the RA2-photo show, the mast (and with that the wind-center CE) was cleverly placed relative ahead, and with two steeroars plunged down aft, he had he had moved back the CLR.
With that constallation he had obtained control over the CE/CLR relation and could run for the wind and at least sail broad reach.
Whether he had or not had daggerboards on the side of bow is outside our interest - but I don't think daggerboards in front-end would be meaningful to use running for the wind over the Atlantic Ocean - on the contrary. Daggerboards in front end are used to move the CLR ahead, as we need, when we are sailing with wind abeam and beating against the wind.
Heyerdahl's captain Norman Baker tells, in a many years later interview, that Tigris "was fitted with a centerboard, as Thor had seen on the jar in british museum" (Ref. J.P.Capelotti: Norman Baker, personal interview, July 8, 2000)
If Tigris was equipped with a centerboard /daggerboard /Guara the Kon-tiki museum doesn't know. That means: that could be or that could be not, but is now impossible to verify, because in acordance with Heyerdahl's Norse tradition, Tigris is pyred.
Tenerife copy of Thor Heyerdahl's - RA II
Not exactly Egypt style. His boat designs were, just as his crews were, a wonderful mixed combination of many cultures. Real international - or transnational.
On his reed boats Thor Heyerdahl used to twist his steer-oars around the shaft - not dip them.
Thor Heyerdahl learned from his Kon-tiki. Not only he learned how a Guara system worked, changing the center of underwater-resistence, when setting boards down between some trunks, but for his next serie of boats - the Ra-serie - he changed the steer-oar system from the force-demanding angling principle to the easier handled twisting system, and he mounted two of the last on his reed boats. These steer-oars at least looked like those of the Egyptians.
Strange enough, he never put a question mark at his square sails. He on all his boats used the Norse styled square sail rigging - and the followers in his wake followed.
As young and strong man Thor Heyerdahl in his raid 1947 used to angle his steer-oar of Kon-tiki = that means, that he forced its blade out of centerline
Next raid he did was with Ra1 twenty years later, and there he twisted his steeroars.
He had learned it.
Remark that Thor Heyerdahl wisely never sailed in cold waters.
A steer-oar can work in more ways:
Dipping the oar as Dirch showed us at Carnon river: With wind across the pointed course and the oar well sustained against the lee side of the craft, a dipping oar/board become a part of the undervaterhull and can changes the CLR = 'Center of Lateral hydraulic Resistance' in a way as balance the leeway of aft versus that of fore end. The dipping oar is of course able to make a static turn.
Twisting the oar, as Thor Heyerdahl did on Ra and Ra2 reed boats. Twist it around the longitudinal axis - just as his Viking ancestors did on their speedy boats.
Twisting work in same way as a rudder hinged on the fore edge of the blade - it act on the streamning water - and thus only when sailing. (- if not rowed sidewards)
Angling or deflecting the oar or oars out of centerline. The angling deviate the streaming of water, just as a classic stern-rudder as therefore take effect when sailing + but too an angling has a static effect placing the oar blade out of centerline, and in that way change the underwater body, at least sailing forward.
Angling is an awful way to steer a vessel. The force needed to push the oar-blade out of line must be delivered by the helmsman, and a strong man is necessary.
But an angling oar was what Thor Heyerdahl employed on his Kon-tiki and what Abora2 + Abora3 used on their reed boat on the Mediterranean + Atlantic seas. But we have to admit that an angling oar is very useful on shallow waters as rivers.
Row the aft end sidewards too is an option. Such an oar mounted in the stern and sustained on the shaft by something like an oarlock could be very useful to promote a static turn, because you can row the aft end sidewards.
- and that was used for positioning lumber rafts drifting down rivers. - as Heyerdahl drifting the logs for building of Kon-tiki:
- and now it is time to have a look at the old Egypt of Pharaoh
Summary of all following Egypt studies and scrutinies:
The Egyptians knew and used the dipping steer-oar!
As seaman and sailor I am convinced, that the Egyptian steer-oar for sailing with wind abeam, was developed in two steps:
In the beginning it was used as a handheld oar/paddle as was set down om lee side of stern to balance the sidegliding of aft-end with that of the fore-end. This gave the pointing of the sail powered craft, just as Dirch demonstrated with his dipping steer-oar:
Bigger boats = more men with each his handheld dipping steer-oar - and here my argument is: That you can't rely on a synchroneous twisting of more independent steer-oars. They dipped!
Later on, when the vessels grew in size and the steer-oar too grew over the size as could be handled by a man. Then this bigger steer-oar were fixed through a "parrel" (a collar, a sleeve) to the gunwale and the upper end sustained against a vertical support, as could resist the sidewarts forces comming from the water press on the oar-blade.
This invention gave new possibilities. By this design they could still dip the blade by sliding down the long shaft through the "parrel" - or they simply could tilt it - and they too could twist the blade, deviating the streaming water - just as a rudder.
The procedure was: Dipping the oar for the main balance of CLR against CE - and later on the sailing twisting it. For example, when they had to compensate a moved CLR, due to crew moving around, a big wave or swell passing or similar.
The use of a fixed "parrel" on the gunwale did, that they still could use a steer-oar even in luff side.
A rather unique and genial created steer-system: to use a steer-oar both dipping and twisting is still not seen from other cultures! Dipping for trim of boat - twisting for steering.
The verified use of dipping the steer-oar.
Tomb of Tia & Tia:
Here are two boats shown on the same picture. The right boat is towing the splendid barge left with the royal couple Tia and Tia on board.
More interesting is to compaire the steer-oars.
The towing is done totally as we would do it today:
The tugged barge at left has its steer-oar dipped down, to move backwards its CLR. Doing so, the barge will not slalom ahead as a water-skier after a boat.
- and the tugboat is steered by the pull from the towing hawser and under the commanded draw from the 20 oarsmen + the sail - and not from own steer-oar, as principally is withdrawed - lifted up.
That the sail is set means, they are sailing up-river against south.
Tomb of Simut
This next image of a towing doesn't verify the observations above around dipping oars - but neither contradict -
The towing here is carried out by two tug-boats and they are probably sailing downstream against north, because here is pure rowing and no sail
The terrible Egyptian way of depicting:
When we study the old Egyptian images whatever they are wall paintings, reliefs or boat-models there are many things as give wonder - as we don't understand today.
In the same way as their drawn persons have twisted their 'upper part', the sails are depicted as braced 'for and aft' - sailing or not. It seems as the artists have a conflict between "how it looks like" versus "how it really is"
Therefore, a study of their boats can give much confusion
For example around their broad yards -
Sometimes we see the ends of yard turned upwards and sometimes turned downwards - but perhaps their yards in fact are curved only in a horizontal plane, as these more modern square sailers as shown herewith ends pointing downwards
- - - or here.with ends pointing upwards
The much confusion is a result mainly of the way to depict at the time of the Pharaohs.
half profile - half front view
Declaration: All scrutiny of objects is made on base of information and pictures available on the Internet
Steer-oars on old Nile river boats
a study of images
What initially caught the eyes comming from Guara-steering of Kon-tikis and via Heyerdahl's reed boats to the world of the Pharaohs on Nile river in the Egypt was the steer oar - or oars - as by place, size and arrangement seemed to have much in common with the Guara sailing as demonstrated on Carnon river with the "dipping" steer oar
- and that observation led us to revise more closely the Egypt sail conditions and knowledge.
Conditions on the Nile river
The Nile river is and has allways been used for transport of goods and people all along the realm, and this natural and simple water transportation system became a key element in the development of the ancient Egyptian civilization, and was therefore too the base for development of water crafts - their boats.
Being an inland channel, the Nile river is considered a protected waterway for sailing, without storms and no high waves.
If hard weather should turn up, the boats could search for shelter along its banks.
As a natural navigation channel and river road along all Egypt, the Nile was favoured by wind and stream. The waterway is known for its special conditions: row and drift downwards with the current against North - and using the steady North or North-Eastern trade wind to thrust the boats upstream against South. Sailing upstream on that river never gave wind directly against. They probably didn't need to beat windward.
And this privileged phenomenon probably in some way has been determinant conditions for the creation of their early sail culture on Nile - and later on Red Sea.
Wood as material for ship-building came late in the Egypt development - imported!
The Egypt river-boat was born on base of rafts of papyrus reed, gaining a long, flat but wide shape. To easen the sailing it grew shaped streemline with pointed and lifted stem and stern - but still with a low and wide body.
Reed boats have no internal room nor hold and therefore all accommodation with crew, cargo and equipment was placed on deck or on a superstructure a level superior.
Because of the existence of these superstructures, the sail was lifted high over the reed body.
They had no ballast, so against capsize they aimed to keep the centre of winds effort as low as possible, why they used low aspect sails and gained sail area by extending a broad canvas. Often as broad as their boat was long.
When later they begun construction of planked wooden boats their boats were shaped acording to their experience from reed boats.
Tomb of Pharaoh Den
Tomb of Ti 2 helmsmen
Tomb of Ti 3 helmsmen
Tomb of Ti 4 helmsmen
Around the steering - a learning from Old Egypt
A dipping steer-oar work very fine in partnership with sail, wind and water. Balancing the leeway of aft-end in relation to the fore-end,
the Egyptians could keep a rather stable course, as all the craft worked as a windvane; so sailing upstream they dipped the oar and found their
course blowing with the wind.
Rowing down river is othervise - we have not the course stabilizing effect from wind on any sail and need therefore more action by helmsman handling a rudder.
We could explain the Egypt steer-oar as a genial combination of trim-keel and rudder - dipping and twisting respectively.
Contributing to the CLR = the center of underwater resistance too the steer oar is under press sidewarts from the water, and it has therefore in some way to be sustained to keep the position.
1): on a smaller boat you need only a smaller steer oar, as a man kan keep in hand. A handheld steeroar is difficult to twist in hand without to fix it to the boat - it will try to "escape". But you can lift and lower it while sustaining it against the lee side of craft, and in this way you can easily balance the leeway of aft-end in relation to the fore-end, as Dirch showed us.
The only thing against that is, that such small and simple boats we have not found pictured in Egypt tombs.
2): A bigger boat need need a bigger oar, as one man can't wield alone, therefore we see pictures with more men side by side each one with a steer-oar in hand.
Boats as pictured in tombs of Pharaoh Den, Ti, Merab and Akmar use two, three or four handheld steer oars. That "nobody" will do, if the oars have to be twisted synchronous - but they will do it, if the oars worked as sidewards waterbrakes balancing aft side-sliding.
If these oars would be plunged down synchroneous by the helmsmen or in in cascade (one followed by other) - is impossible to say. My gues is, that when a drawing show for example three handheld steer oars, these probably was set down in acordance with need decided by the captain 1, 2 or 3
- but in some of the depicted case, a man with braces in hand indicate us, that this boat probably is under a turn (weer), and that justify a maximum maximum steer-oars set down, for maximum move aft the CLR - that means: all oars plunged down aft as turnpoint and waterbrakes against sidesliding.
3): Real big ships as those of the high sea fleet of Queen Hatshepsut have developed a more advanced system, because the dimensions for steer oars grew to a size as no mand could keep in hands.
One big steer-oar tied to the gunwale and the long and heavy shaft of the oar sustained against a vertical pool as permit the steer-oar make the movements
as it may need.
- but due to their handheld tradition, a side mounted steer-oar in same way as a lee-board is bound to lee side, so they mounted another steer-oar on the other side - ready to take over the steering, when shifting windside. Therefore steer-oars in both sides.
By wind abeam I realy doubt if both steer-oars were employed at same time - that cluld be - but by downwind sailing as up the Nile river: both.
4): The ship development went on, the boats went from reed boats to wooden boats, and with same rational thinking as when our old fashioned lee-boards 100-150 years ago joined in the more modern center-board, the two steer-oars joined in one, mounted in a fork in the extreme stern - now working both under wind from both starboard as from port - but the shaft still sustained by a strong vertical pool. The oar-shaft only has to pass over the top of pool to lean against the other side. That was an easy manoeuvre when weering, why the steer-oar has to dip deep down to make a hold in water, as give lee-helm and turn the stern up against the wind. In the moment of brasing the sail over, then the shaft was lifted up over to sustain on the other side of the pool.
But neither that thesis is all the truth. Even looking alike, the viking ships some thousand years later were NOT able to do the same. Their side-mounted steer-oar was tied by a withy through a hole in the blade, as not permitted any sliding down. The nordics twisted their oar, which is natural, but nothing indicate that the vikings have had wit to develope steering by tilting. Nevertheless they proved, that only one steer-oar was needed - their on starboard side of course.
Some of the tomb pictures with stear-oars mounted on the sides don't show any "parrel" on the gunwale to guide the oar-ahaft. That could be an omission of the painter, but that too could be so because these steer-oars was not fixed by any "parrel" system, but only sustained against the gunwale. The operation of such steer-oars could be tilting around the lashing to the topend of the vertical pool - because more of those seems to have a rope - a downhaul to the topend of oar.
If the hull was a reed-hull perhaps it could be rather difficult to fasten a "parrel" to such soft gunwale as of papyrus.
These small observations on tomb pictures does, that we are convinced, that the Pharaoh's steerors NOT ONLY were twisted, as did Thor Heyerdahl on his "Egypt" replicas Ra and Ra2. Heyerdahl seems as have ignored the function af a dipped steer-oar for control of a sidesliding - for trim of boat.
Pharaohnic high sea sailing
The High-Sea fleet of Queen Hatshepsut
The weather conditions on the Red Sea are more or less as on the Nile river with a wind mainly blowing along the sea. But that is a sea - and not a protected water as an inland river with shelter along its banks.
The fleet for Queen Hatshepsut's expedition to the land of Punt was therefore a high sea fleet born to sail on the Red Sea and survive hard weather.
The tomb of Queen Hatshepsut hold some wonderful reliefs as ilustrate in a very detailed way her great expedition til the land of Punt. I don't see those pictures expressing the daily traffic on the river Nile. I se them more as illustrations of the high level of the Egyptian seafaring technology and competence.
There are finds from these boats. Look at hyperlink:
Drawn copy of a relief from the tomb of Queen Hatshepsut - showing ships from her expedition to the Land of Punt.
retouched details from same
photos of the reliefs
Those wonderful reliefs give many details as increase our understanding of that time, they reinforce the impression, that they used the dipping steer-oar principle in manoeuvre of their big boats.
Note the detail on the drawings as are showing that the longshafted steer-oar on all boats are fasted to the gunwale by a "parrel" as both permit a twist of the oar but too a displacement along its axis (dipping)
But the richness of details too tell us many things as we - on background of our present sail technology don't understand to day. For example, our difficulties to comprehend the use of the many stays going from top of mast to the lower yard. Why that?
A prise to those who struggle to regain lost knowledge
In search of the past - the lost lore of Egypt
In spite of the many archaeological finds, relics of the past and pictures from ancient Egypt, we have seen very few sail-experiments carried out to regain the lost lore; but at least 3 deserve to be mentioned. Not necause of their results - but because they tried to find out.
"RA" was a papyrus reed raft replica of Norwegian (Thor Heyerdahl) initiative - fate: shipwrecked
An Egypt mother model - a replica build of local papyrus reed in front of the pyramids in Egypt - sailed out on the Atlantic Ocean 1969
Of course we have got the question of what a reed-vessel crafted and sold by native craftsmen high up in the Andes Mountains may show us around ethnic ocean-sailing some thousands years ago down in Middel East and Africa?
- we are not able to give any reasonable nor logical reply to that - and have to hand the question over to the adventure sailors themselves.
"Abora2" was a totora reed raft replica of German (Dominique Görlitz) initiative - fate: shipwrecked
A Titicaca build totora replica inspired of some rock-carvings from upper Nile - sailing in Eastern Mediterranean Sea 2002
"Min of the Desert" replica of a seagoing wooden ship build on of American (Cheryl Ward) initiative 2008 - fate: unknown, but probably still sailing
An reconstruction of a wreck-find from Mersa Gawasis at Red Sea
The steer-oar on old river Nile
More tomb paintings
Studying details on old wall paintings, old reliefs and old boat models from tombs intensify the impression, that the steer oars on the Egyptian river-boats worked both with the 'dipping principle' as well as the twisting.
Both steering principles could have been employed on old river Nile by the same steer-oar, and being so, skipper could chose what to employ in his situation. Angling of a steer-oar is not seen indicated on any picture.
Upper boat taken in tow
Sennefer with wife onboard a towed barge
if the Eyptians at that time employed "Hobbits" or boys as helmsmen, is nothing verified
Painting from tomb of Sennefer
Lower boat - tugging something
Placed over and under, we feel doubt if this is same convoy as is pictured, as over-under
It seems as that is a rope af some sort, the helmsman have in hand - not a tiller - useful to tilt the oar?
This painting from tomb of Sennefer is shown here as a contrast to that of the tomb of 'Tia & Tia'. The painting rise doubt. Probably it is a tugging convoy, even if pictured over-under. Oposite 'Tia & Tia' there is no clear indication around the use of steer-oar. Another way of towing - or an other way to picture ?
But more pictures perhaps will explain.
The Pharaoh's steer oar
tomb oarboat from 1450 BC.
Tomb of Menna
Battleship of Ramses III
Queen Hatshepsut's Red Sea ship the last two drawings are published by Victoria and Albert Museum, London 1906 - Ancient and Modern Ships, by Sir George C. V. Holmes
Scrutiny and observations
Looking at ancient Egyptian paintings of Nile boats - 3-6000 years old - from pyramids and tombs:
- several of the depicted boats show one central mounted or two side mounted steeroars.
- the steeroars are all rather long shafted and reach over the head of helmsman - sometimes double up.
- the shaft are sustained sidewards and sometimes too tied to a post aft - as to resist some sideforces?
- it seems as each oar has a rope as a sort of downhaul near top-end of shaft.
- we have seen no heavy tiller - and to handle a so big steeroar without tiller seems for us rather impossible.
- the images from Hatshepsut's Red Sea ships show clearly, that the big steer-oars were fixed to the gunwale by a ring
The big mounted steer-oar - great and genial -
When a steer-oar has grown too big to be handled by a man, it in some way has to be fixed to the hull.
What we see we can interpret as a steer-oar, as is kept by a parrel to the gunwale and sustained by the shaft against a vertical pool, and such an arrangement is rather genial.
1): Such arrangement give the option to slide down the steer-oar through a parrel along the cylindric shaft, as often hold a lenght of double height of a man. The parrel does that a steer-oar can work both to lee and wind side. The parrel will keep it to the hull.
2): Being a vertical pool as sustain the upper shaft for sidewarts forces, the oar can be tilted around the parrel and still work sustained.
3): As third movement the steer-oar hold the option to be twisted around its axis in any of the other positions.
4): The combined function seems rather genial, and will work even if the vessel actually is equipped with two steer-oars on the sides of stern - or only one placed in a fork in the sternpost.
A procedure before sailing:
As natural for any seaman, the Egyptians adjusted their steer-oar in two steps.
When a boat departed from wharf, she probably was rowed or paddled out on the water - and out there the sail was hoisted and the boat took headway.
By this headway the bow was pressed into the water and there by the press of water kept without much leeway, while the water was slipping away aft without hindering nothing. That phenomenon is what normally cause weatherhelm - at least when sailing beam reach.
1): Out on the river the first step could be to compensate an awry distribution of load and cargo by dipping (or lift) the steer oar to adjust the leeway of the aft-end alone, thus defining the pointing of the craft. That pointing would then keep-on as stable just as a windvane, as long as the wind were steady, and therefore they could tie the shaft to the pole as seen on the many paintings and release the tiller.
2): If under the navigation the boat should need a minor adjustment of the course to evade something in the water - or because of a gust of wind - or because of moving around the crew, then the helmsman by twisting his oar could steer around, as by a normal stem-rudder. After that he again could release his tiller in neutral, and if no changes in weather conditions the pointing of this 'self steering system' would turn the boat back on that course, as was set in the beginning.
Weer as consequence - not tack
If it really was a dipping oar, that tell us, that such Pharaohnic boats didn't tack - they weered.
They weered by dipping the steeroar deeper, and this action forced the aft-end upwind, and they could swing the sail around with the boat. In the moment of turnning sail over, they guided the shaft of steeroar up and over to the other side of the pool. And so they were sailing on the other bow!
Remember, that the only technical condition for the principle of 'balanced leeway' is to sail by sail = powered by sail.
What they did when only rowing is not clear, they probably twisted the oar - but on the other side, rowing has not the same need for a rudder, as long at the rowers are within direct voice contact with the commanding officer.
something around steer systems
Resumé around steering:
A balanced boat wheather steered by rudder or Guaras don't need more - it is in balance - and if the sail is adjusted for the pointing - she will sail.
Warning: Guara is a steer system and not a keel supplement - the "keel" is the HIGh lateral water resistance of hull - in combination with the LOW forward ditto - no past time nor prehistoric boat have had any type of fin keel
Classic rudder-steering react quick because if angled it work pushing on the streeming water - if there are water as streem. More speed of boat = quicker streem = quicker reaction No speed on boat = no reaction
A balanced sail boat whether by rudder or Guaras don't need more - it will sail on.
Without sail to correct the course a rudder will accumulate the deviation of the boat as it does under oars or with motor - or as when you drive a car.
The angeling steer oar work mainly as a rudder, but is hard to use because of its long arm out to the blade, and it need therefore a strong helmsman to push it out in an angel. This oar is specially useful for rafts in shallow waters as rivers. Is difficult to handle on the sea.
Note that with an aft mounted steer oar it is possible to apply a static turn rowing the aft end sidewarts.
Guara steering is very stable because it work with the actual hydraulic centre of hull versus the centre of Wind (sail). Because of the nature of blowing wind a Guara system react slower than a rudder steering.
A 'dipping board' /'dipping paddle' /'dipping steer-oar' is a special version of Guara-steering. Dipped down it auto-correct a deviation just as a windvane - the wind push you back to the balanced situation defined by the sailcenter CE and the watercenter CLR.
The Egypt steer-oar is rather genial. It combine the Guara-steering with a classic rudder. Dipping the oar as the above mentioned dipping board the Egyptians first trimed the vessel for awry load and cargo adjusting to neutral leeway of aft - and then it was tied. Under sailing it could work as a normal rudder by twisting the blade.
Lift up your steeroar will move ahead your CLR as give 'weather helm' - Deeper down and more aft will move your CLR aft, as give 'lee helm'
A steelyard you can balance by sliding the weight along the arm
A Nile-boat you can point by tilting her steer-oar - back and forth
Tilted up = Minor impact
Tilted down = More impact
Too pushed down aft = Most impact, but need a long shaft - and that had the Nile boats
- and when you hoist your sail, you will learn what what the position of CLR means for your boat -
Here you have to understand 'dipping board' = "Guara-steering" as a principple, where you change the shape (profile) of underwater-hull by setting down an excentric board (a board outside CLR) beeing a daggerboard, sideboard, leeboard or a aft mounted dipping steer-oar. By doing this you move your CLR - move it more ahead or more abaft. Guara-steering play with the static component of the hydraulic resistance and not with the dynamic. To bring in the dynamic component you have to TWIST your oar, as then deflect the water stream - if there is streaming water to deflect. That was what the Egyptians seems to have done - when sailing.
Fore end is kept by the bow wave and aft leeway end is balanced to fore-end by the steer-oars
Boat-1: A boat is trimmed with wind abeam + lee steer-oar HALF down
Boat-2: If you want to go closer to wind - then lift up your oar and let aft-end drift with wind
Boat-3: If you want to sail broad reach, then dip more down your lee steer-oar
Boat-4: If you want to run for the wind, then dip BOTH steer-oars down.
Too many guaras plunged down to give "keel" may dominate (overthrow) your Guara-steering and make it ineffective - making one board more or one less insignificant for position of CLR='lateraldrehpunkt'. That is the same effect, we meet when a rudder-steered craft is equipped with a too little rudder - that will not turn the boat as it should.
Note - just for the case - that Guara-board is a very effective water-brake, and too many guaras plunged down will too have a great influence on your forward sail speed.
And what is said here around the surprising Pharaohnic steer-oar is valid for the Egyptian steer-oar only. No Greek, Carthagean, Phonician nor Roman ship is studied!
Specially for those who are planning a next raid
Always sail with a minimum Guaras plunged down
Try out your speed loss next time in a pool:
Try to swim with one arm vertical - and you will learn it
A modern steer-oar as easily could be changed to the Pharaohnian dipping steer-system: Wharram catamaran - model Amatasi
Advice for whom doubt:
Try out the dipping steer-oar principle - on lee side of any dinghy - or comprehend the meaning of the instruction from Dirch
Steer Oar down = Lee Helm - versus - Steer Oar up = Weather Helm
The mystical Pharaohnic sail
Understanding the broad square sail
The task of any sail is to divide the incoming wind (= the apparent wind) in two: a forward component and a lateral.
The forward component of the wind force will accellerate the craft until the generated hydraulic resistance match it - and then you have your HEADWAY.
The lateral component too will create a movement in the same lateral direction - accelerate the sidevards movement until the generated hydraulic resistance match the winds lateral force
+ but don't forget here to add the lateral force of wind directly on hull + hut + mast and rig, as too contribute to LEEWAY.
The work of those two wind component give you the resulting course through the sea = Headway + Leeway.
The Heritage from the Pharaohs
Tomb of Khaemwaset
Tomb of Huy
Tomb of Huy, lower painting
- at left it seems as it is the same boat pictured twice - sailing up-river and down-river, respectively -
The picture from tomb of Khaemwaset show the upper yard hanging in topping lift - and that hanging could explain the yard-ends as pointing upwards.
The pictures of Queen Hatshepsut's Red Sea fleet too show us the use of topping lift for upper yard - and the result is a rather straight hanging yard, even slim. Too we can see that the braces are fixed half the way out to the ends, and a good explanation for that could be the huge breadth of sail compaired with the breadth of the boat.
The first picture from Huy, the boat with sail, too has her yard ends pointing upwards - but no indication is seen, how it is hanged. But we see that the braces are fixed near the ends of yard, and that we feel a little against the pointing upwards of yards, because the braces haul in downwards direction. But that too could be a question of the Egyptian handling of perspective.
Tomb of Rekhmire
Drawing from Tutankhamon
The boat from tomb of Tutankhamon and that from tomb of Tia & Tia indicate, that the sail not always was limited by the yards - there could be some overflow
In the images we see many ropes from mast top to the yards.
The ropes goes mainly to lower yard - and less to upper.
It seems as a handling system as is forgotten today.
That could be a reefing system - that could be a system to shape the canvas of sail. We don't know and we can't see it.
Such a broad sail seems rather difficult to reef in classic way, reducing the canvas by furling it, tie it to the yard, but there exist the option to reduce the distance between the two yards. The canvas will blow out as a baloon but reduce the active window for the wind.
As explained later: A crab-claw sail we reef in that way - narrowing the distance between the claws and not directly reducing the canvas.
Tomb of Abydos
Tomb of Nespeqashut
Tomb of Tia & Tia - is shown earlier. On the right boat - the tug-boat - is clearly seen the yard tied to an one-poled mast by a parrel - or perhaps both yard are. That indicate that the boat could be a seagoing vessel. Note that the braces are tied to lower yard, what ia a little unusual. Furthermore is shown an interesting detail: the sail is extended upwards over the yard - as a sort of top-sail.
It seems as the Egyptians too used a type of narrow square sail - at least at those pictures - or perhaps it has something to do with the way of drawing a perspective.
Nile boat with sail employing 2-3 steer-oars - the presence of sail probably means sailing up the river against South
Tomb of Merab
Tomb of Kom Akmar
there are several thousands of years between the artists making these imagenes, but nevertheless their triangular way to reproduce sail has something together - and at least the sails don't seems broad - that could of course be the artists' way to express perspective -
Around a broad main-sail
The Egyptian sail - was broad to keep low the center of winds effort ?
The shape of sails from that era generally is broader than heigh - 2:1 or more. If we see other dimensions on the images from Egypt as more square, that could be explained by the handling of perspective by the artist - as shown above.
Nevertheless all oceangoing reed boat replicas after Thor Heyerdahl have had a square square sail around 1:1 or higher + eventually too a topsail. That seems clear nordic style, just as Thor Heyerdahl normaly used.
The broad shape of sail could have been a consequence of the prevailing downwind sailing on the river Nile: maximum sail area and low CE - just as we thousands of years later did with studding sails folowing the trade winds around the world. That seems as a fine rigging for broad reach as the conditions should be up the river Nile.
The windjammers: Broad sail we know from the last end of the clipper era (150 years ago), where we by lowering the center of wind CE have increased the stability - or perhaps made more sails possible to gain more speed.
(Lowest yard was up to tree times the width of ship)
The Nile boats: A broad sail with its low CE=Center of Effort seems a logical consequence of sailing a reed raft where all load and cargo is placed on the deck and no boulder nor other ballast is possible in a bottom
Studding sails as we still use for windjammers.
Take away all the topsails, and you have the broad shape of an Egyptian sail.
The drawing of right studding sail too indicate why the Egyptians used a lower yard. That is simply to keep the broad sail spread out - far outside the hull of craft.
If no lower yard - then there is only left the triangular solution. (shape to compaire to petroglyphs)
I have seen no cross sectioon of any Egypt reed boat, but the pictures of profile indicate same shape of hull as we have on the finds of later wooden boats: rather broad - and for shallow waters low shape and without any keel.
Rigging and ropes
The Egyptian rigging seems very different from what we later developed, and is therefore difficult to decipher with our point of view.
Today we fasten a square sail in 3 points: 1): The parrel, as seize around the mast top +
2): the tack, as is fastened in the wind side to front end of hull +
3): the sheet, as via a rope (the sheet) is tied aft to the lee side - near helmsman.
Those three fastenings transfer all the winds force on the sail to the boat - on square riggers of today.
The yards of old Egypt frequently is shown as build by two or three pieces - natural spars or sharpened out against the ends. The total yard is obviously rather light and flexible.
We too observe that the braces often are tied to the yard half the way out to the point, but that is comprehensible because the long yard compaired to the width of craft - they get a better draw there for the control.
That could be the same for the placing of tack and sheet. The broad sail make it inconvenient to fasten the corner of sail = tack directly to the hull - therefore they have mounted a lower yard as can stretch out the sail and permit a tack fastened on the same low yard but nearer to the mast.
Reefing for hard weather
There is nothing as indicate that the Egyptians used ropes for reefing, and we have seen no clear answer to: How to reef.
An answear could be that they narrowed the distance between the two yards - just as we today do with Crab Claw sail - but nothing is proved.
The many stays from top of mast to - mainly - the lower yard is an example of our wonder. We don't know - but guess that it could have something to do with a reefing system.
Crab claw sail with ropes to draw together the yards = reducing the active window for the wind 'Spilling lines' they are called.
"Traditional design" is an expresion for a modern design without root in any culture
The hull of a Nile boat
Studying paintings, weawings, reliefs and models of Egyptian river reed boats, they verify a principal difference between reed-rafts of Lake Titicaca - and those sailing on river Nile 6000 years ago.
Where the Titicaca indigeneous have designed their hull rather high and compact, the africans at Nile used a broad and rather flat hull shape - probably due to the fact, that no high waves occured on the Nile.
That probably is the reason, why sailing experimental "archaeologist" as Heyerdahl and his followers have chosen the High Andes boat type and sailed on the oceans under flag of other cultures far away from South America high mountains.
Recognition: Everything on sea is possible - and nearly all permitted !
All actual sail experiments have used the Titicaca hull-shape, because it is the only reed boat type as have survived in many years and still is used on the Titicaca lake build and maintained by the same Aymara tribe.
During the next generations after Heyerdahl the boat-wrights from lake Titicaca, have taken care of their new business and have developed new products for their costumers as oceangoing reed-boats and many fantastic creations for turistic use on their own home waters of Titicaca.
The use of Titicaca hull has been "extrapolated" for oceangoing crafts with up to 3 masts - far outside the Titicaca lake.
The craftmanship for these boats does that they "survive" an ocean raid and therefore this Titicaca-crafts are very adored by any "researcher", even his theme is far outside the Andes mountains.
cross sections of classic reed boat from Titicaca Ref. Vikingship museum, Roskilde
The sail on this raft seems rather small for a vessel of this size, specially taken in account, that at 4000 meters altitude a barometer pressure hold only 60% of sea level.
And with that density of air the sail need to be 60-70% larger to yield the same as at level of sea.
The Titicaca sail as is made of totora reed seems to have battens in common with a junk sail - nevertheless I would call the sail of Titicaca a Lug sail - classified as a fore-and-aft
Too - thousands of years ago, in the old land of Egypt, the condition for powering boats by sail was: HIGH lateral hydraulic resistance + combined with LOW forward ditto.
We don't know the exact hull shape of the Nile reedboats more than from pictures - but it seems as the experimental reed boats of the last century do the same: they simply use the Titicaca model and South American technology. They even import Totora reeds from Titicaca togther with their native boat builders for their making experiments to prove the sailing abilties in cultures from other part of the World. That of course seems as a little strange method; but never mind, the Titicaca is a well known and well documented reference as base for building up a modern reed boat lore.
The danger of capsize
Heeling is result of the torque made by wind against lateral water-resistance - in balance with the torque of bouyancy against gravity
The only parameters as skipper on a reed boat can influence is the sail: 'reef or not reef'.
Because of no hold and no deep placed ballast a reed boat by its deck cargo will get a high placed gravitation-centre, as under heeling hopefully keep on the safe side of the buoyancy-centre.
- to reduce the dagerous heeling effect of wind the broad sail with its low center of effort together with the wide and flat shaped V-hull, as move out the boyancy centre to give more resistance against heeling - seems to be a good combination chosed by the Egyptians.
Cross-section of hull
No picture show any cross-section of any boat.
We have no finds of reed boats. But we have finds of wooden boats from Pharaoh Senusret3 and the Khufu ship as show a hull shape rather broad and long. Both have a broad but flat cross section - and they use a plain bottom without any visible keel.
We suppose that this shape were developed for reed boats, but have gone-on among the boat wrights, when changing over to wooden material. Therefore in lack of reed boats knowledge, we have pictured those wooden hulls found together with tombs.
Dashur wooden boat find - from tomb of pharaoh Senusret3 - size around 18m x 6m
Ceremonial barge - Khufu wooden tomb-boat find - Khufu = pharaoh Cheops - size around 44 m x 6m
note that crafts with sail as employ an A-mast probably are riverboats
Some observations around Mast and Rigging
Tomb of Sahure - photo of relief, drawing and model of same boat
A-mast laid down for rowing - probably rowing down river against the Northern wind. Note the trussgirdle. That trussgirdle was what Heyerdahl forgot on his first reed boat RA - as got hogged = lost stem and stern
The Mast and its place
On images of Egyptian boats I have only seen one mast - never more.
The place for a mast is important for placement of your sail centre = "segeldruckpunkt" CE, because that is this, as will blow downwind of your CLR, and thus define the pointing of your craft.
The rule for ALL sail-powered crafts is:
"The CE = center of wind will always blow downwind of CLR = the hold in water, and thus decide the pointing of the craft."
Therefore move which one of thy centres if you want to correct your pointing - but the CE of a square sail doesn't give much options.
If your sail/mast doesn't give the balance, as you originally wanted, you can adjust your CLR by moving your Guaras - or by dipping/lifting your aft mounted steer-oars.
Note, that on these old riverboats of the Pharaoh as well on the much later vikingships, the mast for their lonely square sail is placed rather central in the hull to match the CLR when sailing with wind abeam.
The ideal trim for a monomasted square-rigger is, when the craft sailing with a fresh wind abeam then no fore-Guara is needed and aft Guara /steer-oar is half down. That permit both dip deeper to get lee-helm or lift more to get weather-helm.
If not trimmed well, then try to incline the mast forward (give lee-helm) or aft (give weather-helm) to gain the balance - that operation is easier than to move all mast and rigging.
Mast and both yards with sail are placed om gallows while punting down river against wind.
A beautiful relief as reveal interesting details on equipment, "sheaves" and fastenings in top of mast. The breadth of sail is more than boat length.
Tomb of Ipi
mast-top of Ipi
On the old pictures there generally seems many ropes going from the yards to the top of mast - turning around something and down again.
We don't know for what use , but this picture from ; as the tomb of Ipi at least show us, what a gadget they had in top of mast - a pile of eyes for all the ropes + some bigger eyes for attach of stays and shrouds.
If a tomb picture is showing a craft with an A-mast and sail - then the craft is sailing South up the Nile river - but rowed and mast laid down = she clearly is sailing North against wind.
Around an A-mast.
An A-mast is a very stable mast, as work without schrouds, and even if an A-mast not was known from old-time Europa, it is a part of the heritage from ancient Egypt - in Africa.
An A-mast raised on two wooden shoes seems specially useful for a reed-boat, where it would be rather difficult to mount shrouds.
An A-mast is known as easy to lower and raise, because it will not tilt by waves under the operation, and lower and raise was a manoeuvre as probably was used on each voyage along the river: Sailing upstream with mast and sails raised - and rowing downstream against wind with mast laid down. Much easier to row.
My personal rule of thumb gained from another era, another culture but at least with 20 oarsmen: "lowering the mast when rowing against wind gives double speed"
Hard weather on the sea
My only point against an A-mast is, when reefed down a square sail (not up) there will be difficulties to find a way how to mount a parrel (or rope) to keep the yard tied to - which one of the mast legs? Furthermore any crossbar between the legs will make a parrel impossible.
I have never heard about serious use of A-mast on the sea - outside some experiments.
On the other side, I am not aware, if an A-mast is specially connected to the Nile river as well as Titicaca - as both in some way are to consider as protected waters
To reef down seems therefore a rash decision as will let your square sail hang flappering in a long end of the halyard rope. And to give the sail up - the task to lower a bigger square sail in strong wind and without parrel to the mast is a rather hazardous job for more men, and is in no way regarded as a safe action.
But on the other side, the wind on river Nile are never considered strong. In case of hard weather on the river, they perhaps didn't reef the sail, but turned aside and and looked for shelter along the beach.
There exist other ways to reduce a sail than reef or furl.
An example: A boat with spritsail can take away the sprit, and sail-on with her reduced triangular sail and a flapping edge - and that is a way of "reefing" (without reefs) as you will not find mentioned in many sail-manuals.
With the broad Egyptian square sail is uncertain what they did. Perhaps they could reduce the breadth of sail - making it more narrow by reefing the sides. Perhaps they could approach the two yards and thus reduce the height - just as we often do with the yards on a crab claw sail.
On a sea as the Mediterranean or Atlantic an A-mast seems rather problematic, because on open sea there are no shelter to disposition, and you have therefore to reduce sail, and in the case with an A-mast and one sail only, that is not easy. You need to use a sort of parrel to keep the upper yard to the mast - even when reefing down. The Red Sea fleet was a high sea fleet and perhaps they used one-poled mast and not A-mast. Queen Hatshepsut's fleet for the Red Sea indicate a parrel-arrangement on a one-poled mast.
The Red Sea hold an extent about 200km x 2000km.
An alternative could of course be take totally down the sail and row. The Mediterranean galleys some thousands years later probably did that. As said, the mast laid down perhaps could bring double row-speed.
Note about learning: that the Norwegians first time sailed out with their Tangaroa2 equipped with an A-mast. Their next raid was 10 years later with Kontiki2 equipped with one-poled mast and parrel. Gained experience? - I dont know, because they lost their two Kontiki2 rafts.
Lima - November 2018 - Third edition of this note around the Pharaoh steer system