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Post by jules on Mar 11, 2014 13:54:13 GMT
Congratulations Matti, and Clayton of course. Keep up the good work!
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Post by jules on Mar 11, 2014 13:48:12 GMT
Hi Clayton, It sure would be interesting to see if you, with your model ship building experience, come to different views on Witsen's texts. Make sure you share your thoughts with us. The thread may become even more interesting then. I do not think an English translation of Van Yk is available, never came across one. Alan Lemmers was kind enough to translate Hoving's Witsen-book. If he has Van Yk on his to-do-list next, I do not know. One question though. Why is it that when I have to struggle to come to grips with the Swedish text of Ralamb, no one seems to care, but as soon as one learns that Van Yk is only available in Dutch, the interest stops? Kind regards, Jules
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Post by jules on Mar 11, 2014 13:30:28 GMT
Thank you for the update Fred.
Thought I was finally coming to grips with the matter of framing, when I got surprised again. So the large openings occur at the place where it really matters, above and next to the gun ports of the lower gundeck. This is the place that, in most contracts for warships, is explicitly mentioned: the demand being that the framing had to be closed at this height of the ship. If the overlap of the futtocks was too short here, extra wood chucks ('kalven' in dutch) had to be placed in the remaining openings. At first I thought the side of Vasa was almost completely closed with wood, as can be seen in the diorama-model. But this does not seem to be the case. Openings do occur more often than I thought and at other places than I thought. Am I right in saying that Vasa has an extra fourth tier of futtocks in comparison with the three tiers with other ships? In short: Vasa has a 9-part frame: floor timber, second-, third- fourth- and fifth futtock; other ships have a 7-part frame: floor timber, second-, third- and fourth futtock. The 9-part frame, with the taking into account of a substantial overlap of the adjacent frame parts, would result in an almost closed wooden wall with sparse openings. Van Yk only gives 5- or 7-part frames (Van Yk, 1697, p. 69). I think Witsen, for big ships, only mentions 7-part frames.
I guess I have to wait for Kroum's work in Vasa III to get the complete picture.
The testing program is very interesting. To set a finite element model of the complete ship as your goal, sounds very ambitious. Interesting stuff! This must be a first in archaeology. The ballistic testing program sounds very interesting as well. Tom Ward will surely look forward to that test.
Thanks again Fred.
Regards,
Jules
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Post by jules on Mar 11, 2014 12:29:36 GMT
Thanks for the update Fred. I will prepare for the worst and start saving straight away .
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Post by jules on Mar 10, 2014 21:04:51 GMT
Hi Fred, Agree, when you look at Arnoul's drawing it is immediately clear that round hulls can be built with the bottom based method. Talking about Arnoul. His text is published in Colenbrander's 'Bronnen uit vreemde archieven', but unfortunately Colenbrander did not publish Arnoul's drawings. I have found two of Arnoul's drawings on the net by mere coincidence last week. One of them I included above, the other one is below. When I was in Paris years ago I even visited the Bibliotheque Nationale to have a look at them, but was turned away at the door because I was not an official student. The lady was pretty strict on that, no chance of getting in. One of Arnoul's drawings is in Jerzy Gawronski's 'De equipage van de Holandia en de Amsterdam' and I found the title page of Arnoul's report in Lemineur's 'Les vaisseaux du Roi Soleil', but am struggling to find more. I hardly dare to ask, but do you have any links for me so I can find the rest? Kind regards, Jules
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Post by jules on Mar 10, 2014 20:30:48 GMT
Great stuff Fred. Thank you very much. I suppose the top timbers, or at least the bottom ends, will be placed in the gaps of your test section? Any idea when the tests will be executed?
Regards,
Jules
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Post by jules on Mar 10, 2014 14:30:51 GMT
Hi Fred,
Any updates on Vasa II? In print already? Any idea on what the price tag will read? Two volumes in a slipcase, can't be cheap.
Kind regards,
Jules
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Post by jules on Mar 10, 2014 14:03:56 GMT
Hi Fred, Many thanks for your reponse, again. I will try to use the term 'bottom based' in future. I am surely interested to know what answer mister Soop will give, when you ask him how he came to decide to show the bottom based method in the museum. I think you're probably right in supposing that Landstrom's work had something to do with it. Would be interesting to know to, what mrs. Stolt's reaction was on Soop's decision. I am sure you're right in mentioning some other very well documented shipbuilding methods. My impression is that it's getting harder and harder to keep track with all the new archaeological dicoveries. I am very greatful I told myself I only have to focus on one period and one country: 17th century dutch shipbuilding. That's hard enough as it is. I am glad Vasa is now one of the archaeological sites I can focus on. It is after all the best documented site ever. And the only site of which the main technical guy (excuse the expression), is this approachable. I agree with your advice to Clayton: start with Hoving. But always keep in mind that there are different interpretations of Witsen's texts. Hoving's interpretation is not the only one, and surely isn't always the right one. Kind regards, Jules Ps. I attached the drawing depicting the dutch bottom based method from Arnoul's report of 1670.
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Post by jules on Mar 10, 2014 12:54:32 GMT
Thank you Clayton for posting the pictures of your frames. Very clear. One other reason why I asked this question is that the Vasa-model in the museum's diorama shows a complete wooden wall above the lower wales. Only at the top, the futtocks are shown with spaces between them. According to Fred's answer this is an accurate depiction. I am surprised by the filling out of the bottom with the second futtocks though. Sure, as Fred says, the portrayal of framing in treatises is highly stylized. As is the portrayal of framing in Navy Board ship models. An irregular overlap of the frame parts is a given in actual ship building. Archaeology shows us so. The shipwrights, being highly practical men of course, must have been sensible people: why waste good wood on getting a nice regular view of the frames, which will be boarded up later anyway. But, in the case of Vasa it looks like someone got cold feet with regard to the ships sturdiness. The overlap of the consecutive frame parts seems to be exagerated. In a 'certer' of a 172 foot ship of 1629 an overlap of only 4 foot is prescribed (Van Yk, 1697, p. 159). This is probably a merchant man, but still... Seven foot (almost 2 meters) is a common overlap in big ships of Vasa-size. The dense packing of wood we see in Vasa, is something I never came across reading archaeological reports on dutch shipbuilding. Have I missed something Fred, or is Vasa really an exception? Dutch ships were known for their light build. The english later (around 1670) say that English ships seem impenetrable for cannonballs compared to the dutch ships. When we compare dutch frame thickness with english frame thickness, we have to conclude that the dutch actually did build lighter; this in favour of manoeuvrability and lower depth. On the other hand we have testimonies that cannonballs bounced of the sides of De Ruyter's Zeven Provincien, what implies that even the lighter dutch build was more than sufficient. Or was Vasa an exponent of a new way of enhancing the strength of a ship? Maybe the extra timber was introduced to make the ship impenetrable for cannonballs. Fred's stress tests should be conclusive on that matter. It would be interesting though to compare the results of these tests with the results from stress tests performed on a ship's side that is built according to the lighter, less packed, method. Fred, thank you for sharing your thoughts on the weight distribution in Vasa and its relation to the ship's stability. I do not know if it ever came up in this forum that Vasa is not built according to a certain rule Van Yk mentions in 1697. At the risk that I tread on ground already covered: Van Yk states that no ship should be build higher than twice its depth. The depth being measured at the main frame (hals), from the top of the keel to the top of the end of the beam of the lower gun deck; the height measured from the top of the keel to the top of the railing. When we look at the drawing of the main frame of Vasa, we can see that Vasa is built much higher. The depth to height ratio is almost 1:2,15 instead of Van Yk's maximum of 1:2. The excessive height is probably caused by the height of the second gundeck. This deck is even higher than the lower gundeck. When we look at later 'certers' for threedeckers, we see that the second deck is lower than the first deck. Building threedeckers was something new in 1628, maybe the main building parameters still had to be determined for this type of ship. It's a pitty Van Yk does not explain where his rule originated from. Maybe the lessons learned from Vasa translated into new shipbuilding rules. Fred, looking forward to the post of the framing section. Great! But how sad we have to wait untill Vasa III for all the details of the framing Keep up the good work! Regards, Jules
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Post by jules on Mar 9, 2014 16:29:03 GMT
Hi Clayton,
You're perfectly right in stating that with jumping to general conclusions about hull shapes based on the minimal knowledge of ancient shipbuilding we have, you place yourself on a slippery slope; history has shown so.
Your translations of the dutch word 'groot' are pretty accurate. I would translate the word in the one meaning with 'big' and 'tall', and in the other meaning with 'great' and 'magnificent'. For example: Charlemagne (Carolus Magnus) is called 'Karel de Grote' in dutch.
Good to know you're going to read the thread again. If you have any questions, do not hesitate to put them forward. I can always try to help.
To read up on the dutch ship building methods, Witsen's books (1671 and 1690) and Van Yk's book (1697) are all available as free downloads on GoogleBooks. Just type: 'Witsen Aeloude 1671', 'Witsen Architectura 1690' and 'Van Yk Nederlandsche', and they should pop up without problems. The Witsen 1671 is from the library from Gent university. It differs slightly from the facsimile-versions, but not in the chapters that describe the building methods. The differences only concern Witsen's description of the second Anglo-Dutch war (not very friendly on english dishonourable behaviour); some fragments were deleted in the Gent-version, probably sensored because of the feared outbreak of the third Anglo-Dutch war in 1672.
Good luck with the reading! I am more than willing to help if you get into trouble with interpretation.
Kind regards,
Jules
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Post by jules on Mar 8, 2014 18:33:34 GMT
L.S. Not a new topic, but I have a question about the framing of Vasa. Clayton included a drawing of Stolt and a description of the framing of Vasa by Fred, in his report on building his Vasa-model at www.wasadream.com. _ The drawing of Stolt Clayton showed in his report. When I combine these two sources with a third source, a drawing of Stolt at page 432 of VASA I, it seems to me that Vasa was built in a peculiar way, not corresponding with the 'normal' dutch building method. Let me explain what I mean. In 'normal' dutch ship building an overlap of the frame parts only occurs, broadly, at the bilge of the ship and at the level of the lower gundeck. For the rest of the build, large openings between the frame parts were left unfilled. I hope the sketch below shows what I mean. In the sketch I removed the inner and outer planking at the nearest side. This to show the frame parts with the openings between them. A wellknown 17th century drawing of Sturckenburg shows these openings as well. In contracts the overlap of the frame parts is usually specified as being at least 7 feet or so, which leaves a lot of open space between the keel and the first futtocks, and the first futtocks and the third futtocks. When I look at the two drawings of Stolt, it looks like almost all the space between the futtocks is filled with extra frame parts: almost no spaces between the futtocks are left unfilled, resulting in an almost complete wooden wall at the side of the ship. Prior to the building of his beautiful 1:50 Vasa-model, Clayton used the first two sources, the information gathered from Stolt and Fred, to draw a framing plan. He also arrived at a filled in ships side, filling the spaces between the futtocks with extra frame parts, resulting in the aforementioned wooden wall. And, what's more, Clayton also filled in the spaces between the floor timbers. This resulted in a completely filled up framing from keel to rail over the whole length of the hull. My question is, is this really the case? Is Vasa's framing completely filled up from keel to rail? Since the two drawings of the framing by Stolt only show sections of the ship, I wonder if this filling up-method was used all over the ship. If so, Vasa's framing was built extremely heavy. This, combined with the very heavy, over dimensioned, constructions in the ships interior, would have resulted in a great increase in empty weight of the ship. On top of that, the extra frame parts between the third futtocks, those above the waterline, increase the weight in a position where you would want to save weight, not add it. This must have affected the ship's stability in a negative way. I hope someone can help. Jules Attachments:
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Post by jules on Mar 8, 2014 12:45:48 GMT
And, Fred, thanks again for the elaborate answers. I agree, it's getting more and more interesting as we go along. With regard to Clayton's question: did Kroum find an extra wide floor timber on the main frame ('hals' in Dutch)? I suppose the main frame for Vasa is on one third from the front of the total length of the ship measured over stem and stern. This should be the position where the first floor timber would be located and I can imagine this one being larger. Thank you for the info on the Dutch 'shipwrights' of Vasa. Surprising news. Can we even still call them shipwrights? Witsen for sure does not describe the only way ships were built in the northern way. But al least he provides the only trustable written source we have for this method. The guy wrote down what he saw, measured parts and presented it in great detail. When you're interested in this building method, there is no other way to gather reliable information, then to read his book; hard as it may be. Even when you're Dutch, as I am, his texts are hard to read, and finding things is a nightmare. But, perseverance will be rewarded. One extra warning: go to the original source, do not trust other people's interpretations of Witsen's texts, they're usually wrong. A lot of reference to Witsen is made to defend constructional solutions that, at the least, seem unlikely. Business as usual: when the source doesn't fit the preconceptions, we discard the source, not the preconceptions. The only new sources that can shed light in the dark matters of Dutch ship building, can come from archeaology. And, in this specific case, now that has been determined that Vasa is built according to this method, from Vasa. Don't want to put extra pressure on you, Fred I personally think that there is not another shipbuilding method better documented than the Dutch northern method. Witsen's book gives reliable information, ship models (or still existing photo's from ship models) fill in some of the gaps, and, on top of that, a great supply of archeaological evidence that is expanding every day. Chances to get at least this one right, never looked more promising. Fred, you say that, since no fastenings were found between the floortimbers and the futtocks and between the futtocks, you think that Vasa was not built according to the Witsen-method. In Witsen's method only at one position the first futtocks were attached to the floor timber: at the 'hals'. This set of three frame parts is the only set that has fastenings. The rest of the frame parts are only attached to the planks, not to eachother. I understand that with Vasa this set of three at the 'hals' was not present. Am I right? Thank you very much for sharing your thoughts on the progression of the southern method in the Netherlands. Any ideas on the time frame for the introduction of the southern method? Do you think it was at the same time when carvel-building was introduced in Zierikzee and Hoorn, around 1460? Or much later? Thank you for sharing my view on the 'Hoving-dogma': 'a square ship has to come out of the northern method'. Fred, don't get me wrong, I am in no way saying that drawings had to be used with any ship building method. I think we can be pretty sure that drawings were not used for centuries and still good ships were built. When renaissance came, everything changed. Shipwrights, by learning to write, were more and more inclined to write down the basic principles at first, and their thouights on the subject later. Later, by learning to draw, they saw the advantages of keeping track of their records in a drawing. The problem was however, as it is today, how do you capture the difficult shape of the ship under the waterline on paper? After mastering that, it took another very long time before ship designers made correct predictions for the ships behaviour from a drawing. We're well into the 18th century then. Let's not forget that the 17th century testing approach to ship behaviour, 'we do not know how it's going to behave, so let's drag a model through a water filled basin and see what happens', is still being used in these days. (In Wageningen for example). To build a ship without drawings while applying the northern method, is certainly possible. Witsen shows so. He was trying to capture all the dimensions of all the parts of one ship, by giving these parts dimensions that were derived from the width of the stem. Since he derived the width of the stem from the length of the ship, we can say that he derived all measures for the parts from the length of the ship. After he had done that for one ship, he goes on to say that the dimensional relations for this ship, can be (mutatis mutandis) applied to ships with other lengths and even to other ship types. This approach can also be seen in the 'old' 'table of Grebber', which Witsen included in his book. This table gives the major ship dimensions for a whole range of ships. These dimensions were derived form the length of the ship. For example: length (L): 170 foot, width 42 ft, 5 1/2 thumb (1/4xL), depth 17 foot (1/10xL) etc. Grebber's table also includes measures for determining the shape of certain parts: "the third futtocks hang over at the greatest width: 2 foot 6 thumb." In this way hull design was captured in writing. Witsen expanded on this and tried to capture all the ship parts dimensions in these kinds of divisions. An immense task (he even gives divisions for door posts!), only to be undertaken by a very young person, who is still very ambitious. Witsen tried to capture the shape of the hull of his ship, a pinas, in writing as well. He determined the shape by taking measures on an actual ship while it was being built. He took several heigth and width measurements at 7 stations along the length of the ship. In this way he registered an array of points on the ships hull and gave us a unique insight in the as built shape of the hull of a 17th century ship. Ab Hoving derived his pinas-shape from the points that were given by Witsen. But, unfortunately, some of the points Witsen gave are not correct and have to be corrected to get a good fair hull shape. And this, unfortunately, leads to interpretation again. (Read Kamer and you know what I mean). Ab also took measures of frame parts of the E81-wreck to check if these measures corresponded with the equations Witsen gives. Risky business, since the wreck was dried and not PEG-impregnated like Vasa. Over the many years, all parts have shrunk considerably. And, on top of that, the guys from NISA told me that all the parts were scraped down to remove a 'crust' that had formed. Again, I am looking forward to Kelby Rose's work; Vasa could provide some interesting answers! After posting my last post, I realized that I forgot to mention that the 'spijkerpennetjes' are not the only indicator for the northern method. No fastenings between frame parts is, I believe, another one. No way to build a ship according the southern method, without fastenings between the structural frame parts. Fred, on your book. Delivery time: 3 weeks, a long wait. But, when I finally get to read it, I will keep your warning about the hammerless people in mind. By the way, I love to confuse people with detail. For me everything has to be right to the last detail. If not, something unexpected may pop up that will shatter my illusions of complete perception. I am still brooding on some detailed tech-questions. I will open new threads for those. One more question for this thread though: who decided to show the northern method in the diorama in the museum and in the several other models in the Vasa-museet, and when? He or she got it right years ago and well before 2008/09. I still can't figure out the time line with respect to Landstrom and Stolt. Thank you. Kind regards and a good weekend, Jules Ps. I included a sketch of a section of a ship at the 'hals', when it is ready to receive the first two third futtocks: completely planked up on the inside, still open on the outside. The beams for the orlop deck and the lower gundeck are in place. Attachments:
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Post by jules on Mar 6, 2014 11:08:15 GMT
Thank you Clayton for your response. I am sure the fact that the builders of Vasa were Dutch, helped Landstrom to decide to show the northern 'Witsen'-method. I am surprised to hear from Fred that Landstrom didn't do so because Eva Marie Stolt thought Vasa was built this way. Mrs. Stolt, being aware that the builders were Dutch, concluded that the ship was built according to the southern method. As does Hoving. Hoving concluded that Vasa couldn't have been built with the northern method, because the shape of the hull was too round. Hoving says that ships built according to the northern method can only produce ships with a clear 'knuckle' (as Fred calls it) between the last plank of the floor ('vlak' in Dutch) and the adjacent plank further up. This theory prooved to be wrong. The E81-wreck is very round and built to the northern method. Hoving is still under the impression that the northern method can only produce 'square bottom'-ships. When I asked Hoving last year if he thought if Vasa was built according to the northern or southern method, he said he wasn't sure.
Thank you Fred for your elaborate answer. Very helpful. Just some thoughts:
Sure, Witsen was not a shipwright, but in this case that is a good thing. Being of a wealthy family assured that Witsen could, at a very young age, travel through Europe to study the different shipbuilding methods. And, luckily so, he was very interested in shipbuilding. His father (Cornelis) was at a certain time a member of the Admiralty of Amsterdam and acquired a lot of knowledge about shipbuilding there. As Witsen (Nicolaes) states in his book, his father was even educated by a shipbuilder. So the family was highly interested in shipbuilding, no doubt because they depended on their ships for their trade with Russia and so depended on ships for their wealth.
Fred says the contracts ('certers' in Dutch) in Witsen's work are mainly from the 1620s and 30s, and that's true of course. But Witsen's work also includes contract from later date and a contract for the very large threedecked warship Vrede of 1667. And that prolongues the time frame for the northern method to the 60s. The French spies, Arnoul and Seignelay, prolongue the time frame to the 70s. They have seen the method in the early 70s and even made drawings of it. So it still must have been practiced then.
Fred says Van Yk dismissed the northern method as 'very old-fashioned'. The only quote from Van Yk I could find, that comes close to this, is not that harsh. Van Yk only states that the notherners are 'still' working according to the northern method. What of course makes clear that the southerners were, in the past, working in northern style also, but changed to southern frame-first style later. When? I'm afraid we are not sure yet.
The Rembrandt painting alone, of course, can not be conclusive.
The point that I am trying to make is that when you build according to the northern method, you have to make decisions about form in the early stages of the building proces. For example: the form of the square tuck ('spiegel' in Dutch) had to be determined. (Just ask 7 Provincien reconstructors Dik and Vos what can go wrong with that). One of the other things you have to decide on at the start, is the angle of the scarph in the keel. This determines the rise of the floor along the length of the ship. (Ask Vos again what can go wrong with that). Van Yk shows that records were kept of where the first plank adjacent to the keel ('zandstrook' in Dutch), started to rise above the keel. Van Yk also kept records of the angle the planking made at the tuck. He also makes clear that sometimes, when more ships of one type had to be built, the batten (scheerstrook) from the first ship was saved, in order to use it on the next ship. He also kept records of the turn of the bows. All this, to make sure the knowledge, based on experience, didn't get lost. Later, when the advantages of drawings were recognized, these carefuly guarded 'secrets' were laid down in drawings.
Sure, the shipwrights of those days had enough experience to build a ship from a contract. The problem is: we don't. The Hoving-claim that the building method determines the shape of the ship, is, I am sorry to say, wrong. Even Hoving doesn't have enough experience to build a ship on a contract. I started a discussion on ship-shapes with him last year. He works according the principle: just start building a model, the wood will tell you what is possible and what is not. But, as any model builder will tell you, there is almost no limit to how far you can bend a thin piece of wood when it is wet and heated. I tried and could come up with any shape of hull what so ever. Vos has tried this approach while building the bottom (vlak) of 7 Provincien, and came up with an impossible hull shape. Which had to be corrected by, amongst others, Hoving. Who then used a framing system to determine the correct shape.
Even in the seventeenth century the northern method delivered good and bad ships. But that goes for the southern method as well. In warship building the contracts changed all the time, so every ship was a first built, only based on previous experiences. But, that is true for these days as well. I have been in specialized machine building for a long time, never had a contract with the same specs twice.
Fred, you say that there has been a debate in publications about how Vasa was built. Can you tell me where? I was not able to find anything. Thank you.
Fred, you say that Landstrom followed the Witsen-method. I am not sure of that. The drawing you refer to, does not show the initial frame consisting of a floor timber with the two first futtocks attached to it. Another drawing shows Vasa from behind: the floor planking is laid, and we can see three complete frames. As I explained in my first post, this is not the case with Witsen. Witsen shows that the third furttocks are placed when the ship is in a much further advanced stage of construction. (By the way, the Hoving drawings in the book you refer to, aren't showing the exact Witsen-practice either.)
Fred, thank you for your elaboration on the subject of when the building-method of Vasa was finaly determined. Can I conclude that every proof before 2008/9 is dubious? I think, together with Clayton I believe, the existence of nail plugs, preferably under the floor timbers, forms the absolute proof for building according to the northern method. Theories based on ship form (square is north, round is south) or planking form (carvel is south, overlapping is north), seem to fail. Take the Vasa for example: round but north; first building stage: carvel planking without frame; second stage: carvel planking on one frame; third stage: carvel planking on all frames, fourth stage: overlapping planking on frames.
I have read Kroum's work of 2002. Love it! Is the specific work on Vasa he did, going to be published in the Vasa-series? Or is it already available? Can't wait actualy.
Looking forward to the work of Kelby Rose. Should be very interesting. Any idea when his dissertation will be published? Can't wait for this either.
So, and now I'm going to order Fred's 'Philosophy'. Promises to be a good read.
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Post by jules on Mar 5, 2014 12:02:07 GMT
Good afternoon everybody, Being Dutch I was triggered by the answer Fred gave to Matti's question. Because I wanted to add some comments to the story about Dutch shipbuilding Fred posted, I immediately became forum member. I must first explain that I didn't read Fred's book 'The Philosophy...' (yet), so if I jump to the wrong conclusions I am sorry for that and want to apologize to Fred on forehand. Fred states that in the northern Netherlands no drawings were used. This is unlikely, since Rembrandt painted a picture of a northern Dutch shipwright holding a technical design drawing for a ship, in 1633. I have reasons to believe these type of drawings were commonly used, even in the Northern method, but just didn't survive. Witsen describes in 1671 that he inherited a great deal of drawings from his father when he died in 1669. Only a couple of Witsen's, and other's, drawings have survived, and are saved at the Amsterdam museum. It's a shame treatise writing was not something the Dutch exceled in, as Witsen, being the first Dutchman to do so, had to admit in 1671. That same Witsen gives a somewhat different description of the building process of the northern method as Fred does. Fred says that all the floor timbers were placed after the laying of the floor planks. Witsen describes that at first only a part of the main frame was placed after the laying of the floor planks. This 'mould' consisted of one floor timber and two first futtocks. After placing that mould, the planking was continued to the top-side of these two futtocks. Then two second futtocks were placed at the main frame position to determine the shape of the sides of the ship. After this, a batten ('scheerstrook' in Dutch) was placed to determine the greatest width for the whole length of the ship. Not until then, the other floor timbers and all first and second futtocks were placed. The third futtocks were not placed until the major part of the interior planking was finished, and the beams for the lower gun deck were placed. I included a couple of sketches that, I hope, make clear what I'm trying to say. The first sketch shows the situation at the main frame after the planking of the floor is completed. The second sketch shows the situation at the main frame after placing the 'mould' consisting of the first floor timber and the first two futtocks. The third sketch shows the situation at the main frame after boarding up higher ('boeien' in Dutch) and placing the two second futtocks and the batten. This is the situation right before the rest of the floor timbers and all the first and second futtocks were placed. I hope these sketches also make clear that the shipwright had to determine the shape of the hull at the main frame, before any building activity could commence: the shape of the first and second futtocks had to be determined on forehand. And, what's more... the shape of these parts can be seen on the drawing in the hand of the 'Rembrandt-shipwright' of 1633 and Witsen describes the method to determine the shape of these parts in his description of the northern method in his work of 1671. Fred also states that by mid 17th century the 'bottom based' method was abandoned for large ships. This is not likely. Witsen describes the method in 1671 and repeats his description in 1690. Ralamb describes the method in 1691 and Van Yk mentions it in 1697. Aubin still describes it in 1702 (based on Witsen). French spies mention the method for the Amsterdam Admiralty (where the biggest (app. 170 foot) war ships were built), in 1670 and 1672. I hop I am allowed to ask a question too. Can anyone tell me when it was determined that Vasa was built according to the northern Dutch method? Landstrom already assumed so in 1980, no doubt on indications given by Stolt. Was he the first to publish this? The museum shows the northern method in its diorama of the warve and in several displays of the ship during different stages of the building proces. Were these models made after Landstrom, or before? When I read recent publications, it looks like it has only been recently determined that Vasa was built according the northern Dutch method. I hope someone can help me. Kind regards, Jules van Beek The Netherlands PS. Fred, thank you very much for answering all the technical questions in incredible detail. Where do you find the time?
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