> Here's one of the footnotes:
> "Menzies cites Li Zhaoxiang's Longquan chuan chang
> zhi (1553) and Needham on the subject of Zheng
> He's ships. Both discuss the woods used in
> constructing the junks—cedar, chestnut, fir,
> camphor, and elm—and do not mention teak. See
> Longquan chuan chang zhi, 5:7; Needham, Science
> and Civilisation in China, vol. 4, pt. 3, pp. 411,
> 414. On teak as evidence of Zheng He's vessels,
> see Menzies, pp. 154, 172–173, 201, 227, 309,
> 459."

Cedar, chestnut, fir,camphor, and elm are trees that grow in temperate China (Taiwan had a flourishing camphor-wood export business).

But cedar, fir and camphor have resins that might not have been palatable to shipworms (Teredo), and may also have had a positively anti-bacterial, anti-fungal ability.

Pitch can be a vegetable (resin) or petroleum (bitumen) product, and many wooden ships used it to seal their timbers.

Until the introduction of marine epoxy and lead-based anti-fouling paints here, very recently, the resin from a certain tree was used to seal the undersides of boats.

regards

Richard Parker
Siargao Island, Philippines

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