Making a Kama

The length of the blade is five bu (one bu = approx. 3 mm). Make the width nine bu. Therefore, you must temper [the blade].

The length of the handle is five sun five bu ; or it is a six sun kama when you pound the iron into its place in the wood. Make it eight sun wide, and one and a half bu thick.

For the handle, use Red Cinnamon tree. Nara Oak is also good. The blade is two sided, omote and ura. Sharpen it on both sides.

*Refer to the drawing on the left for the final shape of the Kama.

The text itself is technical, and the final product is drawn at the end of the text. However, the author made a mistake in the beginning of the text, setting the length of the blade at five bu. This seems too short for a blade, and indeed the measurements written next to the drawing show that the blade is in fact five sun.

Another point to clarify is the idea of a double blade. Although the author uses the term moroha, which translates double-blade or double-edge, it does not mean two sharp edges. Instead, we should read it as one sharp edge that is sharpened on both sides.

To no kagi no koto (Entrance Opener)

The length of this [tool] is one shaku (approx. 30cm/1f) two sun (one sun is one-tenth of a shaku). The width is one sun wide. The length of the blade is between one and a half to four bu. The length of the handle is one shaku. The iron should be made thin. Make the iron one sun long, and two bu thick.

The purpose of this [tool] is cut the wall of a castle, or it is used to break the fence when you need to enter that castle.

*In essence, this tool is a saw that resembles the basic shape of a kama.

The author indicates that it is used to cut an entrance in the wall of a castle. This is not a mistake. The base of a castle is made of stones, while the walls, at least in some places, are made of wood. Depending on the location, it could be a thin wall, and an easy place to enter. Also, one should not take these instructions literally. That is, the entrance could be a window or a small service door, in which case only the wooden bar locking it should be cut, thus allowing to open it.

Tetsu no koto (Concerning the Iron)

based on the ability to produce an iron blade as displayed in the drawing,

It is better to make the blade six, severn or eight sun

Concerning kuroro kagi

This tool is used to easily brake the kuroro kagi and enter when the doors to a house or a storehouse are tightly locked. However, there are various sizes of kuroro kagi. If you do not know the type of door, take a middle size tool, which should fit most kuroro kagi.

The tool is made of iron, and the handle is made of cypress wood. Attach a string to the handle and carry it against your hip.

* Kuroro kagi is a set of locks used in doors. Since there is no literal translation for kuroro I kept the Japanese term. The word kagi in this text means "lock".

Although the title of the text, and most of its content refer to kuroro kagi, the subject of the text is the tool for braking the lock. The tool itself is simple to make and to use (see drawing on left). The measurements of the tool are specified next to the drawing.

Concerning Ukibashi (Floating Bridge)

This is a device for a time when you need to cross the moat surrounding a castle, or a water obstacle in haste. Attach [two] ropes in a parallel manner and float them on the water surface. Since it has to be an easy task, use big bamboos to connect the ropes. The ropes to which the bamboos are connected should be thick. Refer to the drawing for details.
(The interval is one or one and half ken)

Attach the bamboos to thick ropes. It is a bridge for people to cross, [but] you can place anything on [the bridge] and transfer it across [the water]. It is a good crossing device for more than one person.

Listening Device

When it is difficult to hear clearly [the sounds] inside a house while secretly infiltrating into it, if you place the kane close to your ear, you will be able to hear the sounds from the house.

These sounds are absorbed by the kane. This is a most useful tool for stealth [entry].

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Insert a metal bar into the kane as shown in the drawing. This [bar] will echo the sounds absorbed in the kane. Always carry it on your chest. It will absorb sounds through one or two thick walls. It will reverberate sounds from fifty or sixty ken away.

Concerning Jiki

This is a method for securing our retreat when discovered by residents while entering secretly into a house. As the need arises, take iron or bamboo and shape it according to the drawing [on the left]. When you need to retreat, spread it on the path of your retreat. [Similarly], spread it in the the path of pursuit so that once stepped on pursuit becomes difficult. Also, there is [a method] of pulling it with a rope. This is a good [method] for spreading when laying an ambush. Refer to the drawing.

Entering a Water Obstacle

This [tool] is used for stealthily crossing a moat [or any water barrier]. Use iron for making the upper round section in the shape of a helmet to be placed on the head. Attach a string on both sides, and at the end of each attach a thin iron plate. It is possible to cross even a fast flowing stream by holding these plates.

Also, if a person is hitting from above, it will not reach the head. Or if arrows and stones are shot at the helmet, they will not penetrate it. It should be good to temper the iron. You should hold the two strings in your hands.