The Visible Chinese Bow
© Stephen Selby, 1999
This article discusses a cross-section analysis of a traditional Chinese bow. A cross-section analysis is a series of cross-sections allowing the reader to look inside an old Chinese bow and see how the materials are put together and how they inter-relate.
Original arrpearance of the bow unstrung and strung. Original estimated draw-weight was about 36 hk (80 lbs)
The original bow was made in North China between 1800 and 1850. There is no maker's mark. When I acquired it, it had broken into two equal pieces in the middle of the grip. By photographing one of the limbs and then using digital editing, I have restored the original appearance of the bow from which the cross-sections were taken. The restoration is shown in the upper part of the picture above. The appearance when strung is in the lower section (the lower bow is of an identical age and design, but is a different bow.)
Birch bark decoration on the bow limbs
The bow's vital statistics are as follows. The bow is symmetrical along its vertical and horizontal axes. For avoidance of doubt, looking at the bow-back from the front, x is the horizontal axis, y is the vertical axis and z is the depth.
|Tip to tip along the belly (bow-bridges absent)||183 cm (y)|
|Tip-to tip along the back (bow-bridges absent)||174 cm (y)|
|Bow tip to string bridge||27 cm (y) (A-B)|
|Bow tip to top of string nock||5.4 cm (y) (A-12)|
|String nock width/depth||1.2 / 1.0 cm (z/y) (B-C)|
|Depth of siyah : tip/midpoint/string bridge||3.3 / 3.0 / 3.3 cm (z) ( points A / D / E)|
|Thickness of siyah (tip/midpoint/top of juntion with limb)||2.1/1.9/2.6 cm (x) ( points A / D / E)|
The measurements are also referenced to the segments marked A - E on the illustration below:
Cross-section analysis of the Chinese bow
Note that the siyah and knee were made of a two pieces of elmwood and that the splice of the knee into the limb could be seen from segment 12 right into segment 8 (about 46 cm). Horn is present from segment 01 to segment 11 (56 cm). Sinew is present from segment 01 to segment 13. Each segment was cut at a 5.1 cm (2 inches) interval along the planes indicated by the black lines.
|Segment 01 x: 3.8 y: 5.1, z: 3.7
The segment shows how the sinew (light gray) has been applied unevenly all around to produce the circular grip. The elmwood build-out at the grip (brown) has contracted through excessive drying and split from the bamboo core. This is probably what caused the bow to break at the grip. The outside of the grip was wrapped in soft leather which has almost all disappeared. The horn (black) at the grip is an additional insert cut from the outer end of the horn.
|Segment 02 x: 4.3 y: 5.1, z: 3.2
The elmwood build-out at the grip (brown) has slipped inward into a void left by shrinkage due to excessive drying. The bamboo core has a vertical crack. The glue between the horn (black) and the bamboo core has served to fill a void between the two materials. There is no sign of any grooves having been cut into the horn/bamboo to increase grip and surface area. Two layers of sinew application (beige) are evident. The birchbark layer is visible at the upper surface.
|Segment 03 x: 4.3 y: 5.1, z: 2.4
Again glue is visible forming a filler between the horn (black) and the bamboo core. But notice also that glue has filled in the crack in the bamboo core showing that the crack must have been present when the bow was made. Three layers of sinew application are visible at this point: but the innermost layer appears to be a very thin layer along the centreline of the bamboo core.
|Segment 04 x: 4.5 y: 5.1, z: 2.2
The split in the bamboo core is pronounced at this point, and no glue has filled it. Glue is no longer filling a void between the bamboo core and the horn. Still no signs of striation on the horn inner surface. At the junction between the bamboo and the horn on the outer surface a 2-3 mm sliver of bamboo has been applied along the length of the limb. Three layers of sinew application are visible, of which the middle on is relatively thin.
|Segment 05 x: 4.8 y: 5.1, z: 2.0
Once again there is evidence of glue in the crack in the bamboo core and glue has also filled a void between the core and the horn. Two layers of sinew application are visible.
|Segment 06 x: 4.9 y: 5.1, z: 1.9
This is the narrowest section of the limb. A second crack in the core is now visible, together with some separation of the core from the horn. The left-hand split in the bamboo has caused the sinew to rupture up to the surface adjacent to it. The narrow bamboo sliver at the junction of the core and the horn can be seen on the left. Two layers of sinew application are visible.
|Segment 07 x: 4.9 y: 5.1, z: 2.0
Considerable filling of a void between the bamboo core and the horn are visible. The crack in the core has widened and the inner layer of sinew application has also split away from the second layer. The outer two layers of sinew have ruptured up to the surface and the outer layer of birch bark has split at this point.
|Segment 08 x: 4.9 y: 5.1, z: 2.0
The bamboo split has caused a rupture through three layers of sinew application and up through the birch bark outer layer to the surface.
|Segment 09 x: 4.9 y: 5.1, z: 2.2
The elmwood end of the knee V-splice is in the centre (dark brown). On the left, the bamboo is firmly glued to it, but some sinew and glue have entered the split, showing that this serious flaw was present at the time of construction. At the upper-right, four layers of sinew application are visible.
|Segment 10 x: 4.9 y: 5.1, z: 2.6
The knee V-splice protrudes above the outer surface of the bamboo core at the top and the first application of sinew served to smooth the contour of the back of the limb. Two layers of sinew application are visible. The bamboo slivers are clearly visible at the outer junctions of the core and the horn. The sinew application at the upper right left a concave surface from which the birch bark layer has become detatched.
|Segment 11 x: 4.7 y: 5.1, z: 2.9
No more horn is visible at this segment. Instead you can see the two white glue lines of the 'little fork', where the siyah is spliced into the knee. The base of the triangle is the point at which the string bridge was glued. Two layers of sinew application are visible.
|Segment 12 x: 2.5 y: 5.1, z: 3.0
The section marks the transition from the base of the siyah to the rectangular upper section, which has a clear shoulder profile at the front of the bow. The knee section is no longer present. Two layers of sinew application are visible.
|Segment 13 x: 2.1 y: 5.1, z: 3.0
This is the base of the siyah. No more sinew or horn is visible: only a decorative layer of birch bark on the top and upper side surfaces. The surface of the siyah has been reddened and a layer of Chinese Shenhsi lacquer has been applied.
This bow was utilitarian, and not particularly well-made. We have found signs that cracks were evident in the bamboo core at the time of construction, as evidenced by seepage of wet glue into the cracks. Whoever ordered it should ask for their money back. These cracks became serious during use. In addition, the bow has over-dried with the result that the elmwood build-out at the grip shrank, causing the bow to fail at the grip.
Mongolian experts, who still use a bow similar in design and size to this one in a very arid climate warn of the dangers of allowing such bows to dry out too much. In winter, they should be stored unstrung along with chilled meat or some other commodity which sweats slightly. Once strung in the spring, they should only be unstrung if it is necessary to do so to transport them.
Last up-dated July 18, 2000