|A sha-ch'uan or sand boat. The big basket tied to the house side is not a dinghy: it's a sea anchor. Illustration by Valentin A. Sokoloff. Click any image to enlarge.|
One type exhibiting the whaleback was the sha-ch'uan, or sand boat, which was in use well into the 20th century. These bluff-bowed Kiangsu traders typically measured 85' LOA and 18.5' beam, and were distinct from larger traders of the same port by generally finer lines.
|Sail plan and interior arrangements of a sha-ch'uan by G.R.G. Worcester. (Please excuse distortion at the bow, due to tight binding on the book from which the image was scanned.)|
|Cross-section of sha-ch'uan. Note the use of frames along with the bulkheads to provide transverse strength. Illustration by Sokoloff.|
|Cross-section of sha-ch'uan. Illustration by Worcester.|
With its extreme tumblehome, the whaleback junk seems to give up a lot of storage capacity compared to Western ship design, in exchange for superior safety. Should the junk's entire upper deck and house be swept away, its hull would remain intact and enclosed. There were numerous incidents of Western-style wooden ships losing their houses in storms and sinking as a result.
Although the sha-ch'uan had no backbone, it did have a substantially thicker central plank that provided some longitudinal strength (and some lateral plane), aided by several half-round wales along the sides and three timbers running full-length along the top surface of the guard deck at both sides of the hatches. Rising well above the waterline was a false stern that extended 7 feet aft of the hull proper, and beyond that was a 10-foot-long stern gallery.
The sha-ch'uan was by no means the only whaleback junk. Two more are shown below, and Worcester's book contains many other examples.
|Although its built-up gunwales make it less obvious than on the sha-ch'uan, the shaohing-ch'uan, or Hangchow Bay Trader, also had whaleback construction. Illustration from Worcester.|
|In contrast to the preceding image, the whaleback construction of this vessel is entirely obvious, its deck being far narrower than that of either the sha-ch'uan or the shaohing-ch'uan. Very heavy wales just below the sheer-chine add great strength to the structure. I have no information on the vessel type, identified by artist/author Bjorn Llangstrom only as being a warship similar to that upon which Marco Polo returned home to Europe.|
The Junks and Sampans of the Yangtze, G.R.G. Worcester, 1971, Naval Institute Press
Ships of China, Valentin A. Sokoloff, 1982, Sokoloff
The Quest for India, Bjorn Llandstrom, 1964, Allen & Unwin