When glued, is sinew more vulnerable to humidity than wood?

Sinsigel · Post by **Sinsigel** » Tue Feb 13, 2007 5:57 am

I began to question such a thing while reading some Korean accounts on archery. The account was from the Annals of Chosun dynasty(A.D. 1392~1910) of Korea.

The Annal is called, "Chosun Wuang-jho sillok" in Korean.
The Annal was fully translated in Korean in 90's,
and is provided on the web freely since December 2005.
(The url of the site is -> sillok.history.go.kr)

The accounts I read were written in 1593 and 1596, during the Seven Years' War(1592~1598) between China, Korea, and Japan.

The following two passages are English translations of the accounts I read.
(Although it is rather awkward to confess, I translated them.)

1): The King asked,

"Did Japanese learn our own method of naval warfare
and the craft of making our own bows?"

Then Kim Eoung-nam(One of the government officials) answered,

"The Japanese did try to adopt our skill of making and using the bow. However, they say, 'It is difficult to shoot such a bow well, because the sinew and the glue get dissolved.' "

2): The King asked,

"Did the Japanese say that they have adopted our own warships, cannons, bows and such?"

Hwuang Shin said,

"Truly, they did adopt our own bows. However, they do not pay much attention to it, because bracing, unbracing, and heating the bow is such a difficult task for them.
About the warship, the Japanese have known such a style since long ago. However, they prefer the swift and light ships to heavy and thick warships. That is why they do not adopt our warships.
They don't use cannons, although arquebuses are always used."

From the accounts above, one can infer that the Japanese had troubles in dealing with the humidity when using the Korean bow.(It is very likely that the bows mentioned above are of sinew, wood and horn.)

However, I've read from one of the Japanese Kyudo sites that are linked in the atarn, that Japanese laminated bow of wood and bamboo, also needed constant care againts dryness, and humidity to some degrees.

If the Japanese have long used such bows in which the materials are glued, why would they abruptly have difficulty in keeping the Korean bow(which is also glued) against humidity?

Is it that sinews and horns are much more vulnerable to moist than ordinary wood, even when both are glued?

The English longbows of yew, too, also needed constant heating and rubbing with wax for succour against moist, according to Roger Ascham.(Although I'm not sure whether it was as laborious as preserving composite bows of horn, wood, sinew from wet.)

Rapsod · Post by **Rapsod** » Tue Feb 13, 2007 3:00 pm

The question why japanese didn't used or made horn bows is interesting question. The making of yumi is also long process that take about 3 year as I read somewhere. Maybe war yumis were made in week or so. That is much faster than making horn bow.

jack farrell · Post by **jack farrell** » Wed Feb 14, 2007 1:01 am

Sinsigel; Maybe one reason that Japanese have favored Bamboo bows over horn/wood/sinew is that before the 1860s anyone employed in the processing of animal parts was of the "untouchable" class. This included leather workers etc. A craftsman was just one step up from the bottom. It probably did not work getting armaments from outcasts. -j-

Bede · Post by **Bede** » Wed Feb 14, 2007 10:50 am

Jack has made an interesting point: did the low status of people working in animal products affect the attitude to their manufactured goods?

Leather was used in armour, saddlery and some types of quivers. Even archers' gloves were made of leather. Horn was carved into various objects. I think it might have been the sinew that they didn't like. That is the only component that I haven't seen in Japanese objects.

It would be interesting to know if anyone who has better knowledge of Japanese technology knows of any use of sinew.

Kyudohund · Post by **Kyudohund** » Wed Feb 14, 2007 3:39 pm

Hi,

the layers of very old Yumis were "glued" with flour and bounded all over the lenght with silktwine and laquered. Hideglue was used a long time too and it was so strong, that To-boundings (To = kind of Rattan) were only used for decoration, or parts were the bow has to be protected, for example at the arrowpass.
In Japan the humidity is never below 70%, but the bamboo-Yumi needs this! Bamboo is a kind of gras and if it gets too dry, it will crack lenghtwise.
My bamboo-Yumi is protected against humidity only on the naked sides with several layers of varnish. Back and belly are not protected. In wintertime, the reflex, when unstrung gets less. In spring and summer, when humidity and temperature is raising up, the reflex gets more again. My japanese Sensei told me the same phenomenon happens with his bow, when he comes to Europe (less reflex) and goes back to Japan (more reflex).
Even Jack is right, but I think the composite of bamboo and wood is the best solution for Japan. I have never seen the much bamboo, than in this country! And japanese bamboo is very straight growing, so ideal for bows and arrows.
Rapsod, its a fairytale, that it takes years to make a Yumi. What takes years is the dryingprocess of bamboo. In Japan they say a bowmaker shall cut 50 bamboos, when his son is born to have good dry material, when he takes over his fathers business. Or another saying is: the bamboo a bow is made, should have the same age as his owner. It is sayed, that dry bamboo gets more smooth as older it is. But this is japanese mentality too.
I never heard, that animal tendons are used in any trade. Even strings for the bows were made of hemp.

Peter

Rapsod · Post by **Rapsod** » Sat Feb 17, 2007 12:13 am

Is that flour made of rice? On this site http://www.tourism.metro.tokyo.jp/english/
I find very good movie about woodworking and I noticed that something like rice flour was used as glue.

Sinsigel · Post by **Sinsigel** » Sat Feb 17, 2007 6:50 am

Thank you all for the comments.

However, to ask one more thing, is preserving hornbows form
humidity much harder than preserving Japanese yumi from moist?

Unfortunately, I have no experience in dealing with any of these two bows.

Kyudohund · Post by **Kyudohund** » Sat Feb 17, 2007 12:12 pm

Rapsod, yes its riceflour.
Sinsigel, I don?t think so. Both kinds of bows have to be prodected from moisture or wetness. Except the whole Yumi is laquered.

Peter

Sinsigel · Post by **Sinsigel** » Tue Feb 20, 2007 6:23 am

Although the thought came to me a bit lately,

I would like to inquire one more thing, if possible.

Is the method of heating the bow - as it is

in many other asiatic hornbows - used in kyudo when preventing

the bow's impairment from moist?

All I know is 'drying the bow' but I'm still not certain about it.

Kyudohund · Post by **Kyudohund** » Wed Feb 21, 2007 8:17 am

No. Only let it dry.

If the Yumis shape needs some correction, it is knead cold in this section when it is strung, but everytime in drawdirection, never in reflex direction. Also, if the worst comes to the worst, it is heated in the section which needs correction and bend very strong and a short time. This should only be done by a very experienced person. My japanese teacher, who is experienced in bowmaking too, did it one time in my presence. He moved the bow at this section over a heating plate and then he put it in a stand, which two people held and bend the bow, I thought he wants to demage it. But .... the bow got the real correct shape.

Orda Khan · Post by **Orda Khan** » Tue Mar 06, 2007 3:32 pm

This is a question that has often had me wondering. Somehow I can not see moisture causing terrible problems, did the the Huns, Magyars, Mongols never experience rain?

Stephen Selby · Post by **Stephen Selby** » Wed Mar 07, 2007 2:39 am

Sure they did; but you can do a lot to protect bows using lacquer or beeswax. I have a hornbow from Grozer. He says, don't worry about rain: just keep it waxed.

S

Orda Khan · Post by **Orda Khan** » Wed Mar 07, 2007 12:09 pm

Stephen Selby wrote:Sure they did; but you can do a lot to protect bows using lacquer or beeswax. I have a hornbow from Grozer. He says, don't worry about rain: just keep it waxed.

S

Yes Stephen, he told me much the same. He suggested that it was not such a good idea to use it in pouring rain. There are many people under the impression that composite bows fall apart due to moisture.

Russ Mitchell · Post by **Russ Mitchell** » Wed Mar 07, 2007 2:39 pm

IF rain were such a problem, the bows would have fallen apart, rather than simply shot weakly. So, for that matter, would the composite prods used in the Teutonic Orders's crossbows.

What this actually makes me wonder is whether rawhide strings might not have been more common than we think. Because that would cause the weakening that chroniclers describe, as opposed to the "this joint has failed and I'm now pulling my bow apart at the seams" problem that nobody ever mentions.

Bede · Post by **Bede** » Wed Mar 07, 2007 8:57 pm

My personal experience in Sydney with composite bows is that they are weaker in higher humidity. I shoot with modern strings usually so the string is not the problem. Here the humidity can vary between 20% to 95%.

I think that rawhide strings were certainly common and they can stretch with moisture, but archers would know when to protect their bows and when they would perform well. Warfare on the steppe was often seasonal. Unless your horses were well fed you would have problems. It was the Mongols who introduced large scale winter campaigns.

In the Turkish and Russian collections, aside from bow cases and quivers, there are also covers for the whole bow and bow case and also for the quiver. The Karlsruhe museum has several too.